Prism Podcast Take Two: Placebos for Pets

My first appearance on the Prism Podcast was way back in 2016, but the hosts, Dr. Grant Ritchey and Dr. Clay Jones were kind enough to ask me back recently to talk about my book: Placebos for Pets? The Truth about Alternative Medicine in Animals. Enjoy!

Posted in Presentations, Lectures, Publications & Interviews | Leave a comment

Fecal Microbiome Testing- Anything to It?

New Ideas in Science
One of the most exciting aspects of science is the discovery and development of new ideas and insights that lead to new ways of understanding and manipulating the natural world. Theories that seem preposterous at first can turn out to revolutionize medicine and other science-based fields.

Sometimes, these theories are greeted with skepticism but eventually prove themselves. The idea that living organisms too small to see exist and can cause disease took centuries to catch on and be empirically validated, but it has led to many of the most dramatic successes in medicine, such as immunization, antibiotics, and doctors washing their hands between patients. The concept that gastric ulcers could be caused by a bacterial infection was greeted with great skepticism in the 1980s, but the first proponents of the idea were awarded the Nobel Prize for their work in 2005.1

Unfortunately, it also happens that some new ideas in medicine are adopted with great enthusiasm and put into practice only to prove dangerously mistaken. The treatment of mental illness by deliberate surgical damage to the frontal lobe (aka lobotomy) also overcame initial skepticism and led to a Nobel Prize. The procedure became common and was performed on tens of thousands of patients. It is now widely recognized as one of the greatest clinical and ethical failures in modern medicine.2

More recently, the idea that many diseases, and even normal aging, were caused by oxidative damage and that antioxidant supplements could prevent disease or retard aging was proposed in the 1990s and initially supported by laboratory and observational studies. To this day, marketing for human and pet foods often includes health claims for “powerful antioxidant” supplements and “superfoods” based on this hypothesis. Sadly, the early promise of this idea has not been fulfilled in real-world studies, which have found few benefits and unexpected dangers in the use of antioxidant supplements.3–11

It is impossible to know in advance which ideas in science will lead to great benefits and which will prove mistaken and lead to equally great harm. Knowing this, a rational strategy would be to approach promising new hypotheses cautiously. A careful, stepwise evaluation from in vitro research through high-quality clinical studies and systematic reviews should be undertaken before we enthusiastically employ new ideas or methods in clinical patients.

Such a cautious approach, unfortunately, often does not suit the human temperament or the psychological and economic incentives to turn hypotheses into therapies and products. In this column, I have written about promising veterinary treatments that have been embraced well in advance of reliable evidence for their benefits, from cannabis12,13 to cold laser14, probiotics15 to electromagnetic field therapies,16 and there are many others. Whether each of these will prove the next antibiotic or the next lobotomy remains to be seen, but the regulatory, economic, and cultural features of veterinary medicine seem to consistently encourage early adoption rather than a cautious, evidence-based approach.

The Microbiome
The latest example of a promising idea that is being turned into clinical tests and therapies well before this is justified by scientific evidence is the concept of the microbiome.17,18 The recognition that microorganisms can be beneficial, even necessary for a healthy organism is a legitimately revolutionary and exciting idea. While it is an exaggeration to say we each carry around more microbial than human cells,19,20 there is no doubt we harbor a complex ecosystem of bacterial, viruses, and fungi that influences our health.18

The very complexity of this system is one of the major reasons simplistic concepts of “good bacteria” and “bad bacteria” or of “balancing” the system with diet changes or supplements are unlikely to be fruitful. We have only begun to even identify the myriad organisms humans and our animal companions carry on and within us, and we have little idea what they are up to. Even crude taxonomic assessments of the microbiome reveal tremendous variation with age, geographic population, diet, and innumerable individual factors. We have a lot of work to do just understanding the composition and activity our microbiomes before we can hope to engineer them to prevent or treat disease. 

Fecal Microbiome Testing
Despite this, there is currently a plethora of products in human and veterinary medicine purporting to do just that. Companies such as Nom Nom Now21 and Animal Biome22 offer fecal microbiome testing for pets to “provide insight into their gut health,”22 “improve your pets’ gut and overall health,”22 and “to provide you with real insights on their unique needs [so] you can have the confidence you’re making the best choices to provide them a happy, healthy life.”21

These companies, not surprisingly, offer supplements, diets, and even fecal microbiome transplantation purportedly guided by the analysis they conduct.

In reality, there is no reliable research evidence showing that these tests provide accurate, actionable information about health or that they can be used to effectively guide dietary or healthcare choices. We lack not only clinical studies validating these specific marketing claims, but even the basic understanding of the determinants of an individual’s microbial ecology and the relationship of this to health and disease. 

A few descriptive studies have provided information about the types of bacteria (other microbes are not routinely identified or studied) present in healthy dogs and cats.23 Other studies have compared the microbiota of individuals on different diets (e.g. cooked or raw, hydrolyzed)24–26 or evaluated the bacterial ecology of individuals with specific health conditions (e.g. IBD and acute or chronic diarrhea, obesity, etc.)27–30

A Canine Dysbiosis Index (DI) has been developed which characterizes differences in fecal microbial organisms between healthy dogs and those with chronic enteropathies.31,32 Though this may eventually be clinically useful, the authors caution, “future studies will need to evaluate the clinical utility of the DI as an assessment tool for microbiota dysbiosis associated with CEs, and the usefulness of tracking microbiota over time and in response to treatment…microbiota is just one of several factors in the pathogenesis of the disease [and there is] overlap in the DI seen between healthy and diseased dogs.”31

These are all important preliminary steps towards a comprehensive and useful understanding of the microbiome, but they do not validate the claims often made for commercial fecal microbiome testing or treatment recommendations based on these tests.

The available research into the human microbiome is much more extensive than what is available for veterinary species. Here is what reviews of that evidence conclude:

The functionality of these microbial communities cannot be easily reduced to a simple summation of potential beneficial and harmful activities…While the premise behind individual microbiome testing is to inform personalized diagnosis and therapies, the current body of knowledge is not sufficient to allow for meaningful diagnoses…irrespective of what a company puts in their marketing material.33

“We are at the very beginning of understanding what one’s microbiome profile means for their susceptibility to or progression of disease…There are far more unknowns than knowns regarding the role of the microbiome and human health.”33

“Mechanistic links of specific changes in gut microbiome structure with function or markers of human health are not yet established; it is not established if dysbiosis is a cause, consequence, or both of changes in human gut epithelial function and disease.”34

Caveat Emptor
While enthusiasm for new discoveries and hypotheses is a necessary part of scientific progress, the premature application of these to clinical patients can be harmful. Treatments based on fecal microbiome testing cannot be reliable when testing methods have not be validated and standardized and the clinical research showing clinical utility hasn’t yet been done. Rolling the dice on promising but unproven new ideas sometimes work out well, but the odds are greater that we will fail to help or even harm our patients if we take shortcuts in the scientific road to understanding.

References

1.        Marshall B. A Brief History of the Discovery of Helicobacter pylori. In: Suzuki H, Warren R, Marshall B, eds. A Brief History of the Discovery of Helicobacter Pylori. Tokyo: Springer; 2016.

2.        Gallen M. A brief reflection on the not-so-brief history of the lobotomy | British Columbia Medical Journal. BC Med J. 2017;59(6):302-304. https://www.bcmj.org/mds-be/brief-reflection-not-so-brief-history-lobotomy. Accessed February 17, 2020.

3.        Yee C, Yang W, Hekimi S. The intrinsic apoptosis pathway mediates the pro-longevity response to mitochondrial ROS in C. elegans. Cell. 2014;157(4):897-909. doi:10.1016/j.cell.2014.02.055

4.        Pizzino G, Irrera N, Cucinotta M, et al. Oxidative Stress: Harms and Benefits for Human Health. Oxid Med Cell Longev. 2017;2017:8416763. doi:10.1155/2017/8416763

5.        Schürks M, Glynn RJ, Rist PM, Tzourio C, Kurth T. Effects of vitamin E on stroke subtypes: meta-analysis of randomised controlled trials. BMJ. 2010;341:c5702. doi:10.1136/BMJ.C5702

6.        Moyer MW. The Myth of Antioxidants. Sci Am. 2013;308(2):62-67. doi:10.1038/scientificamerican0213-62

7.        Pham-Huy LA, He H, Pham-Huy C. Free radicals, antioxidants in disease and health. Int J Biomed Sci. 2008;4(2):89-96. http://www.ncbi.nlm.nih.gov/pubmed/23675073. Accessed December 11, 2018.

8.        Bjelakovic G, Nikolova D, Gluud LL, Simonetti RG, Gluud C. Mortality in Randomized Trials of Antioxidant Supplements for Primary and Secondary Prevention. JAMA. 2007;297(8):842. doi:10.1001/jama.297.8.842

9.        Bjelakovic G, Nikolova D, Gluud C. Antioxidant supplements and mortality. Curr Opin Clin Nutr Metab Care. 2013;17(1):1. doi:10.1097/MCO.0000000000000009

10.      Bjelakovic G, Nikolova D, Gluud LL, Simonetti RG, Gluud C. Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases. In: Bjelakovic G, ed. Cochrane Database of Systematic Reviews. Chichester, UK: John Wiley & Sons, Ltd; 2008:CD007176. doi:10.1002/14651858.CD007176

11.      Paulsen G, Cumming KT, Holden G, et al. Vitamin C and E supplementation hampers cellular adaptation to endurance training in humans: a double-blind, randomised, controlled trial. J Physiol. 2014;592(8):1887-1901. doi:10.1113/jphysiol.2013.267419

12.      McKenzie BA. Cannabis-based remebdies: No reliable clinical research evidence. Vet Pract News. August 2017:38.

13.      McKenzie B. A conclusion on cannabis? Vet Pract News. July 2019:26-27.

14.      McKenzie BA. Uses, Evidence, and Safety of Laser Therapy. Vet Pract News. August 2018:32-33.

15.      McKenzie BA. Probiotics and today’s pets. Vet Pract News. January 2018:30-31.

16.      McKenzie B. Do pulsed electromagnetic field devices offer any benefit? Vet Pract News. January 2020:30-31.

17.      Allaband C, McDonald D, Vázquez-Baeza Y, et al. Microbiome 101: Studying, Analyzing, and Interpreting Gut Microbiome Data for Clinicians. Clin Gastroenterol Hepatol. 2019;17(2):218-230. doi:10.1016/j.cgh.2018.09.017

18.      Knight R, Callewaert C, Marotz C, et al. The Microbiome and Human Biology. Annu Rev Genomics Hum Genet. 2017;18:65-86. doi:10.1146/annurev-genom-083115-022438

19.      Sender R, Fuchs S, Milo R. Are We Really Vastly Outnumbered? Revisiting the Ratio of Bacterial to Host Cells in Humans. Cell. 2016;164(3):337-340. doi:10.1016/j.cell.2016.01.013

20.      Sender R, Fuchs S, Milo R. Revised Estimates for the Number of Human and Bacteria Cells in the Body. PLOS Biol. 2016;14(8):e1002533. doi:10.1371/journal.pbio.1002533

21.      NomNomNow Microbiome – Everybody poops. https://www.nomnomnow.com/site/products/microbiome/. Published 2018. Accessed February 17, 2020.

22.      Microbiome Products Restore Pet Gut Health | AnimalBiome. https://www.animalbiome.com/how-it-works. Published 2019. Accessed February 17, 2020.

23.      Deng P, Swanson KS. Gut microbiota of humans, dogs and cats: current knowledge and future opportunities and challenges. Br J Nutr. 2015;113 Suppl:S6-17. doi:10.1017/S0007114514002943

24.      JS S, E O, JB H, et al. Effects of a hydrolyzed protein diet and metronidazole on the fecal microbiome and metabolome in healthy dogs. J Vet Intern Med. 2016;30(4):1455.

25.      Schmidt M, Unterer S, Suchodolski JS, et al. The fecal microbiome and metabolome differs between dogs fed Bones and Raw Food (BARF) diets and dogs fed commercial diets. Loor JJ, ed. PLoS One. 2018;13(8):e0201279. doi:10.1371/journal.pone.0201279

26.      Sandri M, Dal Monego S, Conte G, Sgorlon S, Stefanon B. Raw meat based diet influences faecal microbiome and end products of fermentation in healthy dogs. BMC Vet Res. 2016;13(1):65. doi:10.1186/s12917-017-0981-z

27.      Handl S, German AJ, Holden SL, et al. Faecal microbiota in lean and obese dogs. FEMS Microbiol Ecol. 2013;84(2):332-343. doi:10.1111/1574-6941.12067

28.      Minamoto Y, Otoni CC, Steelman SM, et al. Alteration of the fecal microbiota and serum metabolite profiles in dogs with idiopathic inflammatory bowel disease. Gut Microbes. 2015;6(1):33-47. doi:10.1080/19490976.2014.997612

29.      Kalenyak K, Isaiah A, Heilmann RM, Suchodolski JS, Burgener IA. Comparison of the intestinal mucosal microbiota in dogs diagnosed with idiopathic inflammatory bowel disease and dogs with food-responsive diarrhea before and after treatment. FEMS Microbiol Ecol. 2018;94(2). doi:10.1093/femsec/fix173

30.      Suchodolski JS, Markel ME, Garcia-Mazcorro JF, et al. The fecal microbiome in dogs with acute diarrhea and idiopathic inflammatory bowel disease. PLoS One. 2012;7(12):e51907. doi:10.1371/journal.pone.0051907

31.      AlShawaqfeh MK, Wajid B, Minamoto Y, et al. A dysbiosis index to assess microbial changes in fecal samples of dogs with chronic inflammatory enteropathy. FEMS Microbiol Ecol. 2017;93(11). doi:10.1093/femsec/fix136

32.      Suchodolski JS. Diagnosis and interpretation of intestinal dysbiosis in dogs and cats. Vet J. 2016;215:30-37. doi:10.1016/J.TVJL.2016.04.011

33.      Staley C, Kaiser T, Khoruts A. Clinician Guide to Microbiome Testing. Dig Dis Sci. 2018;63(12):3167-3177. doi:10.1007/s10620-018-5299-6

34.      McBurney MI, Davis C, Fraser CM, et al. Establishing What Constitutes a Healthy Human Gut Microbiome: State of the Science, Regulatory Considerations, and Future Directions. J Nutr. 2019;149(11):1882-1895. doi:10.1093/jn/nxz154

Posted in Science-Based Veterinary Medicine | 8 Comments

NextGen Podcast-Vaccination & Vaccine Hesitancy in Veterinary Medicine

Here is a podcast interview I did recently talking about vaccination and vaccine hesitancy in veterinary medicine. Enjoy!

Posted in Vaccines | 1 Comment

More Good News on CBD and Canine Arthritis

I have been trying to keep up with the clinical trial literature evaluating cannabis (primarily CBD) in veterinary patients. There is a lot of research happening right now, so it is challenging to keep current even on this limited subset of studies, but fortunately I know some folks who are much more involved with CBD research and can pass along new evidence as it gets published. So far, clinical trials show promising results for treatment of arthritis pain in dogs and not so promising results in one study evaluating CBD for treatment of canine epilepsy. Another small study looking at treatment of arthritis in dogs (along with some lab animal and human effects) has recently been published which strengthens the case for use of CBD in these patients.

Verrico CD, Wesson S, Konduri V, et al. A randomized, double-blind, placebo-controlled study of daily cannabidiol for the treatment of canine osteoarthritis pain [published online ahead of print, 2020 Apr 24]. Pain. 2020;10.1097

This study included a relatively small number of dogs (20) divided into 4 groups: placebo, two different doses of plain CBD, and a type of CBD packaged chemically into little globules called liposomes, which can influence how some drugs are absorbed and distributed in the body. The study used subjective assessment of arthritis symptoms by both veterinarians and owners, and both groups were blinded to the treatment each dog received.

The study found statistically significant, and potentially clinically meaningful improvements in most measures for the high-dose and liposomal CBD and no improvement for the low-dose CBD or placebo. The lack of a placebo effect is always a bit of a concern since such an effect is usually seen in pain studies in dogs, and the absence of a caregiver placebo can be a sign of a methodological problem in a study. However, the apparent dose-response, with greater improvement seen at higher dose, is a good sign since this is commonly seen with most pharmaceutical effects. There were no signs of adverse effects or abnormal changes in blood tests.

The non-clinical measures in mice also showed some changes in modulators of inflammation which support a plausible mechanism for clinical effects, a necessary step in building an overall picture of the value of any drug therapy.

While this is a small study, and no single trial is sufficient to make a definitive judgment, this is good quality evidence which is consistent with other existing studies, and it strengthens the case for CBD as a potential treatment in dogs with arthritis. All of the usual caveats apply- this doesn’t support any of the hundreds of other claims for CBD; many over-the-counter CBD products have uncertain ingredients and poor quality control, so even if CBD has real benefits they may not be seen with poorly regulated products; there is stronger evidence for the benefits and potential risks of NSAIDs, and these are still a first-line treatment for arthritis in appropriate cases, along with weight management and other existing strategies. On the whole, though, the evidence is getting better and better, and the value of CBD for dogs with arthritis seems likely to be quite high.

Posted in Science-Based Veterinary Medicine | 8 Comments

Are Unconventional and Raw Pet Diets Becoming More Popular?

One of the most popular subjects for discussion and debate in pet health for many years now has been the relative merits of commercial pet foods and unconventional diets of various types, including homemade cooked and raw diets, commercial raw diets, vegetarian diets, etc. Some pet owners and veterinarians have concerns about the safety and health effects of commercial diets, though only some of these concerns have any real evidence to support them, and most of the negative claims about commercial pet food are unsupported or simply inaccurate. 

Most veterinarians are more concerned about the safety and nutritional adequacy of unconventional diets. Homemade cooked diets have been repeatedly shown to be unbalanced and nutritionally incomplete if not formulated by veterinary nutrition specialists. Diets incorporating raw meat, both commercial and homemade, present a serious risk of food-borne infectious disease to pets and humans (123456). Vegetarian diets may be adequate for dogs if carefully formulated, but they are likely unsafe for cats, and there are no demonstrated benefits for either species. 

Subjectively, there seems to have been an increase in pet owners’ interest in and use of unconventional diets n the two decades I have been in practice. While most do still feed at least some commercial cooked foods, many are experimenting with homemade or raw diets despite the risks and lack of evidence for any benefits. A new study has tried to assess how popular such diets really are and how this has changed over time.

Dodd, S., Cave, N., Abood, S., Shoveller, A., Adolphe, J., Verbrugghe, A.

(2020) An observational study of pet feeding practices and how these have changed between 2008 and 2018 Veterinary Record Published Online First: 18 June 2020. doi:10.1136/vr.105828

The authors began by reviewing the literature for previous studies that investigated pet owners’ feeding practices. They then conducted an online survey asking pet owners about their use of conventional, homemade, and raw diets. The results suggest that while most people still use conventional and cooked diets, the inclusion of raw and unconventional diets is increasing. There also appear to be some regional differences in feeding practices. The table below summarizes the comparison of the current study with past reports.

Overall, the results suggest that most pet owners feed some conventional commercial food to their pets. However, it also appears that a higher percentage of owners include homemade cooked or raw foods as some or all of the diet for their animals. Well over half of the respondents indicated they feed at least some raw animal products, and in some locations (e.g. Australia) this appears to be even more common.

There are, of course, significant limitations to this study. The data was collected by an online survey shared on social media. This obviously represents a subset of the pet owning population, and it is particularly easy for passionate advocates of one extreme or uncommon type of diet or another to promote the survey and create the false impression that their views are more widespread or popular than they really are. Advocates of unconventional diets or medical approaches always seek to gain legitimacy by exaggerating the popularity of their views (despite the fact that popularity isn’t a measure of truth or scientific merit anyway).

However, it is worth considering that this study might reflect at least some real growth in the popularity of unconventional diets, including raw foods. This possibility has to be taken seriously given that such diets, and the unscientific reasoning or distrust of mainstream scientific evidence and opinion that often lies behind them, represent a real threat to animal health. In the absence of any reliable evidence for health benefits from such diets, the risks are clearly not worth taking, and any evidence that this message is not being heard or understood by pet owners should motivate veterinarians and proponents of science-based nutrition to work harder at educating the public about the risks and benefits of various feeding options.

Posted in Nutrition | 10 Comments

Rabies Challenge Study Results Are In–What Do They Mean?

The subject of vaccination is one of the most common, and sadly most controversial topics I address on this blog. As I have said many times, vaccines have both risks and benefits, and the balance between these must be assessed in the context of the risk of specific diseases, the scientific evidence concerning specific vaccines, and the health and needs of individual patients. The available evidence is overwhelming that vaccines do far more good than harm for most pets, and following the most recent, evidence-based guidelines is almost always the right choice for most pets.

However, fears of vaccines that are out of proportion to the real risks are widespread, and unfortunately there are some veterinarians who encourage such fears. These doctors rely mostly on anecdote to support their anti-vaccine claims, but some do cite scientific evidence (accurately or, more often, inaccurately) to make their case. Some critics of standard vaccine practices even attempt to produce their own research evidence to support their approach. This research frequently has flaws or limitations which make it not particularly reliable or illuminating. 

One example I have discussed in the past is a study by Dr. Jean Dodds, a noted proponent of various kinds of pseudoscience, from raw diets to unreliable lab tests. She published a study challenging common vaccine practice in 2016 in the Journal of the American Holistic Veterinary Medicine Association (JAHVMA), a niche journal dedicated to pseudoscience. This study purported to show that small dogs could be fully immunized, and would have fewer adverse effects from vaccines, if given half of the usual 1mL quantity of most vaccines. In reality, the study was of such poor quality that it showed nothing of the kind and really provided no useful information, merely the illusion of evidence to support Dr. Dodds’ personal beliefs.

Dr. Dodds has now published another vaccine study, in concert with a couple of academic vaccine researchers and a lay person who advocates for limiting vaccination because she believes her personal dog developed cancer because of a vaccine. This study has received a lot of press coverage, associated largely with efforts to raise money to fund it and with advocacy efforts to restrict rabies vaccination. It has been in progress since 2008, and the results have been eagerly awaited not only by vaccine critics but by vaccination proponents such as myself hoping for some useful evidence to help guide our rabies vaccine practices. Unfortunately, once again the study has limitations that render the results of very little use.

Dodds WJ, Larson LJ, Christine KL, Schultz RD. Duration of immunity after rabies vaccination in dogs: The Rabies Challenge Fund research study. Can J Vet Res. 2020;84(2):153-158.

The stated purpose of this study was to demonstrate that the duration of protection from rabies vaccination is far longer than the three years most vaccines are proven to be effective and to provide support for changing legal rabies vaccination requirements and common veterinary practices. While there are potential risks to rabies vaccination, as for all effective medical therapies, these are rarely common or serious, and there is yet no real evidence that extending the interval beyond three years will reduce the risks meaningfully without also increasing the risk of rabies for some dogs. 

Nevertheless, it is always useful to get additional high-quality research evidence to help guide clinical practice, so this study could have been useful. From a logistical and ethical perspective, studies looking at the effectiveness of rabies vaccine are difficult because you have to expose some dogs to certain death and others to the risk of death from this fatal disease in order to test the protection offered by vaccines. That was done in this study, but it ended up adding only very little useful information to discussions of rabies vaccination practices.

The study initially included 100 dogs, a huge number by veterinary standards. However, 35 of the dogs were not used at all, and only 35 were part of the challenge study directly testing the duration of protection provided by rabies vaccination. These were divided into several groups given different vaccines and tested for protection at different times.

Vaccine A
This was killed, adjuvanted vaccine of the type commonly used for dogs (though the specific vaccine is no longer manufactured). Dogs were vaccinated at 12 weeks of age and again at 15 weeks of age. This is not a standard or recommended protocol used commonly in practice. Most dogs are vaccinated once at 12-16 weeks of age and then given a booster one year later, so this does not really reflect common practice. Presumably this was done because the dogs needed two vaccinations to be fully immunized, and the authors did not want to wait 1 year to give the booster and then have the challenge stage of the trial delayed by that year.

At 6 years and 10 months after the initial vaccination, the vaccinated dogs were exposed to rabies, as were 5 unvaccinated dogs in the control group. The USDA standard for proving a rabies vaccine good enough for use is that it must porrect at least 88% of vaccinated dogs. In this trial, all 5 dogs survived the challenge. However, only 2/5 control dogs developed rabies, showing that the virus used for the test was not sufficiently active (natural rabies infection kills 100% of infected animals). Therefore, these results can’t tell us if the test dogs were truly protected at this time point.

At 8 years after final vaccination, another challenge was done with 5 vaccinated and 5 unvaccinated dogs. This time, all of the unvaccinated dogs died, showing the test virus was active. However, all but one (4/5 or 80%) of the vaccinated dogs also died, so at this time the vaccinated dogs were no longer adequately protected. 

The investigators also looked at whether or not vaccinated dogs could generate an appropriate antibody response to a booster vaccine given 6 years and 1 month after initial vaccination. None of the dogs had an antibody titer considered protective at this time (and neither did the unvaccinated dogs, of course). A booster of the same type of vaccine generated a protective antibody level by 14 days after the booster I 90% of the vaccinated dogs (and 30% of the unvaccinated controls). The authors also gave some dogs a booster using a recombinant rabies vaccine made for cats, and though this would not be done in actual practice, this also generated a protective antibody response in most dogs.

Vaccine B
The authors also vaccinated several groups of dogs with another rabies vaccines, this one marketed as not containing the preservative thimerosol. This reflects Dr. Dodds antivaccine biases, since vaccine opponents often claim that thimerosol is a dangerous toxin despite the fact that it has been used extensively and shown to be safe in humans and animals for decades. This vaccine is not widely used, though apart from the missing preservative it is equivalent to common rabies vaccines.

Of the dogs vaccinated at 12 weeks and again at 15 weeks with Vaccine B, 5 were included in the initial challenge study at 5 years in which all vaccinated dogs survived but so did 60% of the unvaccinated dogs. Another 5 from this group were challenged at 6 years and 7 months after final vaccination, of which 4/5 (80%) survived. Another 12 of these dogs were challenged with rabies at 7 years and 1 month, of which 6/12 (50%) survived.

What Does It All Mean?
Unfortunately, the answer is, “Not much.” The study used two rabies vaccines that are not in common use and an initial vaccination protocol that differs significantly from standard practice, so it’s not the best model for studying how rabies vaccination usually works. The numbers in each challenge group were quite small, and the death or survival of a single animal could drastically change the apparent percentage surviving or dying the challenge, so any broad generalization about the dog population in general would be unsupportable.

The first challenge studies at about 5 and 6 years can’t be interpreted since most of the unvaccinated dogs survived the virus challenge. Even though all of the vaccinated dogs lived, this doesn’t prove that we should be given rabies vaccines every 5 or 6 years instead of every 3 years. This might be an effective interval for many dogs, and there are some other sources of evidence that suggest rabies vaccine protection might often last longer than 3 years, but we still can’t say this with any confidence. Given the very severe consequences of being wrong, namely the death of many dogs and potentially of people exposed by these dogs, and the lack of evidence that extending the interval by a few years would have any meaningful benefits, this portion of the study doesn’t really provide a reason to change current recommendations.

Of the dogs challenged at about 6 ½ years, 20 percent of them died, which is more than the allowable 10-12% under the USDA guidelines, and certainly more than we should thjnk of as acceptable. In this study, that 20% was only 1/5 dogs, but in a population of millions of pet dogs vaccinated every year, that could represent a huge risk to both our pets and the human population. 

This is reinforced by the portion of the study looking at antibody titers, since none of the 10 dogs tested 6 years after vaccination had a titer above the established protective level. This suggests we would be wise not to wait as long as 6 years before given rabies boosters to our dogs. Similarly, of the dogs challenged at 7 years, 50% died, so we certainly shouldn’t think of this as an acceptable interval between vaccinations. 

All in all, this study undermines the claims some vaccine critics make that a single rabies vaccination is all dogs should ever need. In fact, it reinforces concerns that extending the interval between vaccines will put more dogs at risk from rabies and do more harm than good. Even if 4-5 years between boosters is as effective as 3 years, it is very unlikely this change would have any significant benefits given that the risks of rabies vaccination is very low, and considerably less than most vaccine critics suggest. An interval of 6 years or more looks very likely to increase the risk of rabies significantly based on this study. 

Some vaccination critics are already suggesting that even though this study didn’t turn out the way they wanted, it still supports their general argument that we should vaccine less often than 3 years and use titers instead of vaccination. However, in the published study the authors are careful to point out that the results do not establish that a given titer level is sufficient to prove a dog is protected nor that any specific interval beyond 3 years is safe, even though they still believe this is true. 

Even though I believe the risks of current rabies vaccination practices are often exaggerated, I am disappointed that the time and effort put into this study, and the dogs sacrificed as part of it, did not provide useful evidence to clarify the overall duration of immunity provided by standard vaccination practices. I also hope the authors will be vigorous in challenging the use of their work to argue for changes in rabies vaccine laws or common practice since the data do not support such changes even if the authors personally believe they are warranted.

Posted in Vaccines | 9 Comments

New DogRisk Study Compares Risk of Allergies in Dogs Associated with Raw and Processed Foods

The subject of raw diets is a constant and controversial one in veterinary medicine. The controversy stems mostly from the fact that some people are passionately committed to the idea that raw diets have health benefits, but there is no scientific evidence to support this and plenty of evidence showing uncooked food increases the risk of parasitic and infectious disease.

Just this week, there was another series of cases in which people suffered serious foodborne illness due to contact with raw pet food. This is a frequent phenomenon, and there have been many studies in the last 10 years showing raw diets present real health risks to people and pets. There is no comparable body of evidence showing any health benefits. There are, however, a few studies like this that would claim to do so:

Hemida M, Vuori KA, Salin S, Moore R, Anturaniemi J, Hielm-Björkman A. Identification of modifiable pre- and postnatal dietary and environmental exposures associated with owner-reported canine atopic dermatitis in Finland using a web-based questionnaire. PLoS One. 2020;15(5). doi:10.1371/JOURNAL.PONE.0225675

This study comes from the DogRisk group, which I have written about previously-

This is a group of veterinarians and nutrition researchers led by Dr. Hielm-Bjorkman, a faculty member at the University of Helsinki. The organization is independent of the university, and it appears to focus on generating evidence to support raw diets, supplements, and a few other alternative health practices (such as acupuncture). The team is composed mostly of academic researchers, both vets and PhDs, working on issues of animal nutrition. Individually, they have legitimate credentials and research topics, but as a group they seem pretty dedicated to proving a set of pre-existing beliefs about raw diets rather than investigating the subject impartially. 

This paper appears to fit into the group’s campaign to validate their pre-existing beliefs about raw diets. The stated goal was to evaluate potential causal factors associated with the presence of allergies in dogs, including the diet of dogs with or without allergies and the diet of the mothers of these dogs. The data come from an online survey of owners, and it is currently only available in Finnish, confining the study to a narrowly limited population not representative of pets or pet owners in other places. 

Such online owner surveys are deeply unreliable. The diagnosis of allergies and the details of diet history are based entirely on the recollections and reports of pet owners, most of whom have establishes beliefs about pet health and nutrition and little or no scientific training in these subjects. Many such studies, in human and veterinary medicine, have shown that such information is often biased and not consistent with findings in more controlled research. The authors of this study actually report that almost 13% of the responses had to be discarded because they appeared to be “robot answers,” though it isn’t clear how this was determined. Clearly, this is a dubious source of data to begin with.

The authors compound the problem of reliability by imposing their own arbitrary and biased definitions on the variable they claim to be examining. They divided diet into two extreme categories: 1. A non-processed meat-based diet (NPMD) and 2. An ultra-processed carbohydrate based diet (UPCD). These are artificial categories that reflect the ideological bias of the researchers, not the reality of the kinds of foods dogs are actually fed. 

“Non-processed” is meaningless unless the dogs are basically eating whole prey and plants, which it is highly unlikely many of them are doing. The term “ultra-processed” is also a value judgment that implies a negative health impact that has not actually been shown to exist in pet foods. And commercial kibble, which is likely what the authors are referring to here, is not accurately described as “carbohydrate-based.” The carbohydrate content of commercial dry diets varies dramatically, as does the type of carbohydrate (from simple sugars to complex fibers). The nutritional value and potential health effects of commercial diets will also vary greatly based on these differences, and lumping them all together in this artificial category is not a legitimate scientific research approach; it is simply a way of stacking the deck in favor of the result the authors want to get.

The authors claim they are using a validated system of nutritional categories from human nutrition science, known as the NOVA Classification. This system, however, is not meant to apply to pet foods, and the definitions of “processed” used in the system have no relationship to how pet food is prepared. Here’s what the WHO says about the NOVA classification:

A number of commonly consumed processed foods and drinks [are] certainly or probably implicated in obesity and various chronic non-communicable diseases. These include energy- dense food products, “fast foods”, “convenience foods”, soft drinks, sugary drinks, various refined starchy foods, processed meat and salt-preserved foods. [note, none of these categories is relevant to properly formulated commercial pet diets]

Food processing in itself is not the issue. One obvious reason is that nowadays, practically all food is processed in some sense and in some way. The term ‘processing’ (like the term ‘industry’) is very general and therefore not helpful, and so judgements of foods simply because they are ‘processed’ are not meaningful. Food scientists and technologists and food manufacturers are right to emphasize the benefits of originally ancient and also relatively novel processes such as drying, non-alcoholic fermentation, chilling and freezing, pasteurization, and vacuum-packing. 

Confusing commercial pet diets with human convenience and snack foods because they are both produced by large industries and come in packages is misleading. The intent and formulation methods are vastly different, and the superficial similarities are not a legitimate foundation for assuming they have the same health impacts.

The NOVA classification also makes no reference to raw or uncooked meat and, in fact, states that, “These methods and processes are designed to preserve natural foods, to make them suitable for storage, or else to make them safe or edible or more pleasant to consume. Many unprocessed or minimally processed foods are prepared and cooked.”

Beginning this study with a distorted misinterpretation of terminology not intended to apply to commercial pet diets is a reflection of the underlying intent and bias behind the research. Other evidence of the authors pre-existing convictions come in the form of discussions of the “natural” diet of dogs as “carnivores” (myths used to promote raw diets which I have addressed before) and irrelevant reference to celiac disease in humans as a way to imply grains are unhealthy for dogs.

There is no apparent attempt to control for these biases in the methodology. The researchers designed the survey, defined the variables of interest, and had total freedom to create and conduct the regression analysis as they chose. It is well-established that such a lack of methodological control for bias leads to research which reflects the beliefs of the researchers more than the underlying reality of nature. 

This study was also funded in part by a company selling raw dog food. Funding bias is a known problem in medical studies, and while it is not an excuse for ignoring or dismissing research out of hand, it does require methods built into the study design to limit the impact of funding source on results, which were quite limited in this study. It is also common for proponents of raw diets to claim most veterinary nutrition research is useless because it is funded by pet food companies. It will be interesting to see if this community is consistent in ignoring this paper, which supports their belief, or if they prove interested in funding bias only when it helps dismiss research they don’t agree with.

Bottom Line
This study is a great illustration of ideologically motivated research. A group of scientists committed to a pre-existing belief design and conduct a study tailor-made to provide evidence supporting that belief. The authors do acknowledge some limitations to their project, but they consider them minor and accounted for, and they ignore some of the most significant problems I have mentioned here. 

This study fits into a series of efforts by this same research group to validate their belief in the benefits of raw diets, and unfortunately it doesn’t contribute much to actually understanding the pros and cons of raw foods for pets because it doesn’t contain much objective, reliable evidence. It will undoubtedly be useful as marketing r propaganda for proponents of raw diets, and much like research studies done on homeopathy, it confuses rather than clarifies the issue.

Posted in Nutrition | 7 Comments

Racism in Veterinary Medicine

This post is a bit outside the usual topics I discuss on this blog, and I have no doubt I will get angry responses and admonitions to “stay in my lane.” But at a time when America is, once again, being forced to confront our long-standing failure to deal effectively with racial inequities built into our society and institutions, I feel an obligation to address the reality that veterinary medicine is very much a part of this problem. 

The facts are relatively straightforward: Over 95% of veterinarians are white in a country where about 80% of the workforce is white. Imagining this is an accident rather than the result of systemic racism is naive or disingenuous. Acknowledging an injustice is critical to rectifying it, and we cannot shy away from clearly and directly describing an unjust reality if we seriously hope to change it. Veterinary medicine is quite possibly the whitest profession in America, and this is like any problem in that we won’t be able to fix it if we don’t acknowledge it.

A common first reaction when a group of mostly white people is asked to consider the issue of racism within their community is defensiveness. There is a misconception that racism is limited to explicitly bigoted and discriminatory behavior by individuals who openly dislike people of color, and since few of us fit that caricature, it is easy to dismiss our own role in perpetuating racial inequities. However, racism is typically more insidious and systemic than this. It is not a problem of a few “bad apples” but a feature of how the barrel is built and maintained. 

As an example, AAVMC data shows that the proportion of white applicants to veterinary colleges in 2016 (78.1%) was roughly the same and the proportion of white students in those colleges (78.3%). This suggests that explicit racial discrimination in admissions is not a major barrier to recruiting underserved groups into the veterinary profession. This is encouraging both because such discrimination would reflect poorly on the profession and because it would be a clear violation of federal law.

However, despite this, the representation of individuals from some underrepresented groups in both the applicant pool and as students in veterinary colleges is still dramatically lower than the proportion of the population identifying as members of these groups. For example, African Americans make up about 17% of the U.S. population but only 4.4% of applicants and 2.5% of veterinary students. The situation is actually worse than it sounds because about 70% of black veterinarians are educated at one school: Tuskegee University College of Veterinary Medicine, a historically black college. The underrepresentation of African Americans in veterinary medicine has persisted despite discussion about it and efforts to remedy it going back to the 1970s, and it is evident that there are strong and pervasive systemic factors behind this.

There have been some successes in addressing discrimination in veterinary medicine. Historically underrepresented groups have increased as a proportion of the student population. 

Women, in particular, have gone from a small minority to a large minority in veterinary schools, and they are now a majority in the profession and beginning to achieve parity in some areas, such as leadership roles at veterinary schools, though there are still disparities in pay and other indicators of equity.

We have actually reached a point where the overrepresentation of women in some areas of veterinary medicine is problematic. Contrary to a common assumption, diversity is not inherently a concept intended to exclude white people or men, and true diversity in the profession requires a better balance than currently exists in the gender representation among veterinarians. 

However, it is important to remember that the historic underrepresentation of women in the field was the result of both individual and systemic discrimination, and the influx of women into the profession can be seen, at least partially, as evidence of effective strategies for combatting this. The underrepresentation of men in veterinary schools today, on the other hand, seems unlikely to represent the same kind of discrimination since it is implausible that a group still in a position of privilege and power in most areas of American society would somehow be excluded by deliberate or systemic discrimination in one small domain like veterinary medicine. 

There are likely complex factors involved in the decline in male applicants to veterinary schools, and many of these may involve the ways in which the profession is portrayed and perceived in the culture as well as economic factors. For example, as veterinary medicine has shifted from a focus on food and working animals to companion animals, it may be seen more as a caring or nurturing profession which cultural stereotypes classify as more appropriate for women (women are also overrepresented in pediatrics and nursing, for example). Veterinary medicine is also among the lowest-paid of the medical professions, and men may be more likely to pursue higher-paying jobs (female-dominated professions in general tend to pay less than male-dominated occupations). The growing scarcity of male role models, at least in companion animal medicine, may also be a contributing factor.

The issue of gender representation is relevant to the subject of racism in veterinary medicine both as an example of how historic discrimination can be overcome and also how complex and indirect the factors influencing the recruitment of different groups into the profession can be. The underrepresentation of African Americans in veterinary medicine, for example, is sometimes written off as a lack of interest. This narrative suggests that black people aren’t as interested in animals as white folks and so are less likely to want to be veterinarians. The issue of cultural differences in attitudes towards animals is a real and complex one, but as a facile way of denying racism as a cause for underrepresentation of African Americans in veterinary medicine, it is not convincing.

For one thing, this doesn’t explain the consistent underrepresentation of other minority groups, such as the Latinx community. The idea that multiple historically marginalized groups all just happen to not be interested in veterinary medicine is not plausible. More likely, the paucity of applicants from underrepresented groups is related to a lack of examples and role models from those communities that make the profession seem welcoming and possible for them, the disadvantages such groups face in terms of education quality and opportunity well before veterinary school, the rising cost of a veterinary medical education, and a constellation of other factors. Such factors have certainly been demonstrated to be associated with underrepresentation of African Americans, for example, in other professions, and addressing these barriers has improved diversity in these cases.

Clearly, we have a lot of work to do as a profession if we are committed to real diversity. White people must take an active part in this work, leveraging our power and privilege no support equity and improve opportunities for those who have been, and still are denied then. We must remember that diversity is not a zero-sum game in which one group must “lose” for others to succeed. No one, least of all people of color, is suggesting lowering standards or implementing some sort of active “reverse discrimination” against white people. The goal is to ensure that everyone has a chance to explore and fulfil their potential, and that barriers to this which apply disproportionally to historically marginalized groups are removed. Diversity ultimately benefits the profession and all of us in it.

As a relatively old, white, male veterinarian, I can acknowledge the injustice that has favored those like me without feeling that the effort and struggles I endured to get where I am are being invalidated. I may be good at my job, and I may have earned my place through hard work. But many people who are just as talented, just as hardworking, and who have even greater obstacles before them are as deserving but have been denied the opportunities I have had. There is no question that being white has been an advantage in my journey. It does not diminish me to acknowledge this, but it does engender a responsibility to contribute to a more just future.

Resources-

Navigating Diversity and Inclusion in Veterinary Medicine; 2013, edited by Lisa M. Greenhill, Kauline Cipriani Davis, Patricia M. Lowrie and Sandra F. Amass

Minority Student Perceptions of the Veterinary Profession: Factors Influencing Choices of Health Careers; 2008, by Dr. Evan M. Morse (thesis)

Unity Through Diversity; 2006, Final Report of the AVMA Task Force on Diversity

Cultural Competence in Veterinary Practice. V.Kiefer, K. Grogan, J. Chatfield, J. Glaesemann, W. Hill, B. Hollowell, J. Johnson, D. Kratt, R. Stinson, and K. Urday. JAVMA. 2013 243:3, 326-328 

A Business Case for Diversity and Inclusion: Why it is Important for Veterinarians to Embrace our Changing Communities.  L Kornegay. JAVMA. May, 2011.

Cultural Competence Education; Association of American Medical Colleges.  2005

The Attitudes of Minority Junior High and High School Students toward Veterinary Medicine. A. Asare. J Vet Med Educ.  2007 34(2): 47-50.

Tying Art and Science to Reality for Recruiting Minorities to Veterinary Medicine. PM Lowrie. J Vet Med Educ. 2009 36(4):382-387.

Racial, Cultural, and Ethnic Diversity within US Veterinary Colleges. Greenhill, LM, PD Nelson, and RG Elmore. J Vet Med Educ. 34(2): 74-78.  2007

Posted in General | 17 Comments

Evidence-based Veterinary Medicine in the Real World

Vets and vet students often get the idea that evidence-based veterinary medicine (EBVM) is a purely academic thing or isn’t practice in general practice. As a GP firmly committed to this approach, I like to debunk those myths whenever possible.

I recently spoke to the senior veterinary students at my alma mater, the University of Pennsylvania School of Veterinary Medicine about EBVM in practice, and gave some examples (including how EBVM has helped our practice in responding to COVID-19). Here are the slides for these presentations.

Posted in Presentations, Lectures, Publications & Interviews | 5 Comments

Our Veterinary Hospital Experience with the COVID-19 Pandemic

This an article I wrote for Veterinary Practice News about our hospital experience with the COVID-19 pandemic. Every veterinary clinic and hospital will have their own unique experience of this time, but I suspect much of this will look familiar to others in the profession and to pet owners. One element of the experience that is relevant to my work here on SkeptVet is the importance of a critical, flexible, evidence-based approach, which has helped us tremendously in dealing with the unprecedented challenge.

From the trenches: How life has changed since COVID-19 came into our lives: What veterinary medicine is like at Californina’s ground zero

The hospital is quiet as I walk in at the start of my shift. The usual bustle of clients, staff, and animals has been replaced by empty hallways and only a few masked doctors and nurses going about their work quietly, careful to keep their distance from each other. I stop at the screening table and start my day by taking my temperature. It is under 100.4 F, and I have no cough or other respiratory symptoms, which means I can work today.

I set down my belongings at my desk and go to change my clothes. I wear scrubs every day now, and I have a pair of dedicated work shoes that stay at the hospital. I also have a collection of beautiful cloth face masks sewn by one of our employees—I wear a clean one every day.

At the end of my shift, all of my work clothes go into the laundry. When I get home, everything I took to work stays in the garage. I pass quickly through the house and take a shower before I greet my family. I am especially mindful to keep my distance from my elderly mother, who lives with us, and to handle neither her dishes nor her medications. My wife does that now, since she has been working from home and hasn’t mingled with people outside the house for the last month. This is the new routine of our lives, one familiar to countless others since the arrival of COVID-19.

Operating in California’s ground zero
I have worked at the same practice for 16 years. We are an unusual hospital; an independent general practice with 30 veterinarians and more than 150 other staff, open 24 hours a day seven days a week. Because we are located in Silicon Valley, an affluent area in Santa Clara County, Calif., we able to offer services not always found in first-opinion practices, such as orthopedic surgery, in-house ultrasound, cancer therapy, and advanced emergency and intensive care. Our location, however, also means we are in the center of California’s novel coronavirus outbreak. COVID-19 has changed not only my morning routine, but nearly every aspect of the work and lives of our practice, staff, and clients.

Santa Clara identified the first case of COVID-19 in the county (and the ninth in the U.S.) in early February. A sentinel surveillance study in early March confirmed community spread was already occurring, and the county began instituting social distancing measures on March 11. Initially, these involved closure of some public businesses and recommendations for people to avoid large gatherings. By March 16, Santa Clara and surrounding counties had issued shelter-in-place orders, essentially banning people from leaving home except for specified essential activities. On March 30, further restrictions were added and the shelter order was extended into May.

This rapidly expanding public health crisis and frequent changes in restrictions on public activity has presented a tremendous challenge to our hospital. We see hundreds of patients and have dozens of doctors and nurses in the building every day. We also operate on an open hospital model, meaning clients can stay with their pets for nearly every aspect of their care, from being present for outpatient procedures, to watching surgeries, to sitting with hospitalized patients as long as they choose during daytime hours. While this model is unfamiliar and startling to many in the veterinary profession, it has been an intrinsic component to our practice culture for decades. Having clients present throughout the hospital is something we, and our clients, have come to expect.

Doing things differently
The coronavirus outbreak and the public health directives aimed at combating it have forced us to reevaluate our models for patient care, client service, and personnel management; our financial structures and processes; and even our role in the larger public health landscape. Such a comprehensive reevaluation of every aspect of our work, conducted rapidly and in an ever-changing environment, has been challenging, even painful. However, it is also an opportunity to take stock of who we are as health-care providers and as a business, and to grow stronger as a result.

In addition to seeing patients, part of my job in my practice is to drive and support continuing improvement in the quality of care we provide, and to help maintain staff and patient safety. I am the designated evidence-based medicine nag, responsible for translating scientific research into useful tools and actions we can take to better care for our patients. This includes training new veterinarians; developing protocols and guidance documents; conducting clinical audits and evaluating patient outcomes; and many other quality-improvement activities.

One particular project that has proven timely was my effort last August to promote more effective hand hygiene throughout the hospital. I expanded the accessibility of hand sanitizer, put up posters throughout the hospital illustrating proper handwashing technique, and of course nagged everyone to wash their hands. Lately, some staff members have jokingly suggested I may have gone a bit overboard in trying to make my point.

Of course, despite my efforts to support a culture of proactive, science-based medicine, we could not realistically have been fully prepared for what the coronavirus pandemic has required of our practice. However, this culture has proven useful in making the many adjustments necessitated by the virus in the face of limited evidence and great uncertainty. We already had a system for identifying reliable sources of information and translating imperfect science into clinical practices. Our doctors, staff, and management were long accustomed to incorporating scientific data into their daily activities and to adjusting their work routines based on changes in the available evidence. The habits of flexible, pragmatic evidence-based medicine have served us well.

The specific changes we have made in how we handle clients and patients, how we protect staff, and how we have adjusted our business to cope with the legal and economic realities of the pandemic may or may not be useful to other practices in other contexts. However, they illustrate how the methods and habits of evidence-based medicine can help a veterinary practice respond to an unexpected and unfamiliar crisis.

Applying evidence-based medicine
We began our response to the pandemic by developing and collecting policy documents in one central location. With a rapidly changing environment, and frequent adjustments to policies and procedures, it was crucial the most current protocols be readily available to everyone on staff. Protocols were developed by a group representing all the teams within the practice, including doctors, technicians, and management. Input was sought from as many people as practicable, which frequently helped to identify oversights and errors, as well as to generate the widest possible array of ideas and options.

Although veterinary practices are considered essential services in our region, and therefore allowed to operate despite the restrictions of public health orders, we realized early we would need to limit our work to urgent and emergent cases, and to defer most elective and well-pet services to reduce traffic through the hospital and exposure risk to staff and clients. We developed a triage tool to help staff decide which services qualified as essential and which would need to be deferred. This was similar to the tools developed by the British Small Animal Veterinary Association (BSAVA) and other veterinary organizations.

Our initial strategy for reducing exposure risk was to screen both staff and clients for relevant clinical symptoms and for fever. Though this strategy is imperfect, it has been utilized and found helpful for identifying COVID-19 cases in some circumstances. We also set up social distancing guidelines within the hospital.

However, we quickly realized these measures were insufficient, and we made the difficult decision to ban all clients from the hospital, apart from exceptional circumstances such as euthanasia and critical acute emergencies. Clients now wait in their cars, and nurses in appropriate personal protective equipment (PPE) triage pets outside and then bring them into the hospital. All subsequent communication with clients is by telephone until the pet is returned to them outside.

This has been especially difficult for us, and for our clients, as it conflicts with our culture as an open hospital. Being separated from a sick pet is an unfamiliar experience and an added stress for clients who, like all of us, are already dealing with the impact of the pandemic in their personal lives. Most clients have been understanding of our goals in protecting them and our staff, but in the short-term, this has been one of the most uncomfortable consequences of the outbreak. The long-term effects on our culture and relationships with the community are a source of concern for all of us.

Watching out for one another
Having restricted client access to the facility, the greatest risk to our own health became each other. It is often impractical to maintain effective physical distancing when working together treating patients. In response to this risk, we have continued screening staff for symptoms and fever, and we have done what we can to keep people apart in the workplace. The extra hand sanitizer I ordered in September and the handwashing protocols I posted have turned out to be quite useful! We have also had many lively discussions about the use of masks as a tool for reducing the risk of coronavirus transmission within the hospital.

The evidence concerning the value of masks in reducing spread of respiratory viruses is limited and contradictory (e.g. 123). It seems unlikely they protect the wearer from exposure, and they can actually increase risk if improperly used. However, wearing masks may reduce the risk of an infected person from spreading the virus, particularly since asymptomatic shedding apparently occurs commonly. It is also important to remember PPE is in short supply, and the risk and needs faced by human health-care providers are much greater than ours.

Early in the outbreak, our hospital donated a substantial portion of our masks, gowns, and gloves to a local hospital, as well as offered our ventilator for use in human patients through a database set up by the American College of Veterinary Emergency and Critical Care (ACVECC). Our remaining PPE is under lock-and-key, to be used only when strictly necessary.

Ultimately, the mask debate was settled for us by a directive from public health officials recommending the use of cloth masks in addition to physical distancing methods in businesses still operating. We are fortunate to have several employees with handicraft skills who have been making beautiful and functional cloth masks for our staff and their families. These employees have had plenty of time for such projects, as another necessary response to the pandemic has been to reduce staff in the hospital and to decrease payroll expenses.

The limitation of cases to urgent and emergent care has dramatically reduced revenue at our hospital. Veterinary small animal medicine is an unusual hybrid, being both a health-care industry and also, in many cases, a small business enterprise. Large-scale corporate ownership and consolidation of veterinary practices is certainly widespread and growing. However, the average small animal practice in the U.S. employs only two veterinarians and three to five veterinary technicians (2019 AVMA economic report). Though my practice is unusually large, we are still a much smaller business than most human health-care providers.

The drop in revenue, as well as the need to reduce the risk of coronavirus spread between employees, has necessitated dramatic cutbacks in staffing at our hospital. These reductions have involved unpaid leave, furlough, and various mechanisms dictated by the financial and regulatory environment in which we operate. Most doctors, myself included, now work one week and are furloughed for one week. Other staff members are limited in the number of shifts they can work in a month. So far, we have managed to avoid laying off any employees, but the threat to our livelihood adds to the stress imposed by the risk to our health.

Overcoming disruption
As in veterinary practices around the world, our employees are struggling to face not only restrictions on their movement and activities, cancellation of planned events, closure of schools and loss of childcare, and other disruptions in their personal lives, but also a loss of income and of the security and purpose of their jobs, which for many are as much a vocation as an occupation.

Like many in the developed world facing isolation and uncertainty due to the pandemic, the role of virtual communication in our lives and businesses has expanded greatly. We have a dedicated private Facebook community for staff that has provided great support for many of us during the days we cannot work. We are, in some ways, closer than ever since we are learning more about each other’s homes and hobbies, partners and pets through this virtual community.

We are also making use of online communication tools as a hospital. In April 2019, we began offering video visits for clients. These have been a useful way of triaging patients and managing minor health problems that do not necessarily require an office visit. As a result, we had a reliable system and experienced telemedicine staff in place when the pandemic began. Since the outbreak began, the U.S. Food and Drug Administration (FDA) has relaxed requirements for a veterinarian-client-patient relationship to facilitate such use of telemedicine tools. We now have two full-time telemedicine doctors, and this has proven an excellent means of maintaining contact with clients and preserving revenue, while reducing hospital visits and exposure risk to employees and pet owners.

Since the beginning of the pandemic, our clients and staff have had questions about the risk of infection to our patients and the potential for pets to spread the virus to humans. Despite the enormous, unprecedented scientific research effort targeting COVID-19, there is surprisingly little evidence to help answer these questions.

Very few studies have specifically evaluated the susceptibility of companion animals to SARS-CoV-2 or the risk for transmission from dogs and cats to their owners or veterinary personnel. Individual case reports and limited research evidence suggest dogs are very resistant to infection and illness (456). Cats and ferrets appear to be more susceptible, but the risk of transmission to humans is still considered low (6789). There is essentially no research evaluating the potential for pets to act as fomites or mechanical vectors for COVID-19 (10).

We have developed guidelines in our hospital for handling pets from known COVID-19-positive households, both those with or without symptoms, and there are a number of such guidelines available from veterinary organizations (11). However, all of these are based on extremely limited evidence, and it will be some time before we fully understand what risk, if any, pets may pose to veterinary professionals or the public. This is an example of the common, but necessary challenge of practicing evidence-based medicine when data is sparse. The key is to be aware of the evidence that exists and its limitations, to take pragmatic and proportional action based on what the research says, and to be flexible and prepared to change our practices as the evidence develops.

There is reason to believe all the effort and sacrifices we have made as a hospital, as well as that of government agencies, businesses, and individuals in our area, have been effective. Though Santa Clara County was one of the first centers of community spread of SARS-CoV-2 in the U.S., cases have not grown as fast here as in some other places, and the health-care system has so far been able to cope well with the number of COVID-19 patients (1213). We appear to be “flattening the curve,” a rather dry and abstract phrase that represents a meaningful reduction in human suffering.

As a hospital, we have been fortunate to not yet have any known cases of COVID-19 among our staff. However, the reality is that it is only a matter of time before someone we know is infected, or falls ill, or perhaps even dies as a result of this disease. The mitigation measures we have taken and have been imposed throughout our area and around the world are not sustainable in the long term. With a highly virulent virus spreading through a completely naïve population, no proven effective treatment, and a vaccine well over a year away by some estimates, the disruption this disease has brought to our hospital and our lives will persist and evolve for a long time to come.

However, we have also learned a great deal about our capabilities as individuals and as an organization. We have been reminded of the value of creating an adaptive, science-based practice culture and of the habits and methods of evidence-based medicine. We have learned from the ways in which we were prepared to cope with this unexpected crisis, and from the ways in which we weren’t. COVID-19 has reminded us of the essential nature of veterinary medicine, not only in companion animal health and food safety, but in human health as well. It would be difficult to find a more dramatic validation of the One Health concept than our current situation.

The months ahead, perhaps even years, will continue to be challenging because of this virus, but we have tools and knowledge not available during the last century that have allowed us to respond more quickly and effectively, and this has made a very real difference in the lives of millions of people. We can and should do better in the future at preventing, predicting, and responding to such public health threats, and with the lessons learned now, I have no doubt we will. My hope is that as a hospital community and as a profession, we will emerge from this crisis stronger, smarter, and better equipped to face such challenges in the future.

Posted in General | 13 Comments