Antibiotics & Antibiotic Resistance

Key Takeaways

  • Antibiotic Resistance is a growing problem
  • Antibiotics are vastly overprescribed, and many times the proper diagnostic tests aren’t being conducted beforehand.
  • Everyone (veterinarians and Pet Owners) is incentivized to continue overprescribing antibiotics.
  • Few New Antibiotics are in the development pipeline
  • Unless directed by a Veterinarian, you likely don’t need to use an Antibacterial Shampoo. 
  • Ask your veterinarian
    • Are antibiotics are necessary?
    • Is there a diagnostic test that can confirm the need for antibiotics
    • Can they wait until the susceptibility results come back?
    • Are the antibiotics being prescribed as a precautionary measure?
    • What should I be on the watch for so we can pick up the antibiotics if they become necessary?
  • Slowing or reversing the growing trend of antibiotic resistance requires both veterinarians and Pet Owners to be stewards.

Antibiotics

Antibiotics can be amazing. They are a significant reason why the average human life expectancy has gone from around 48 years in 1900 to around 78 in 2022.

We previously wrote about some of the longer-term effects of antibiotics and steroids on the microbiome of our dogs and cats; How they

  • Can slow the maturation of the gut microbiome in the young
  • can take several months for the microbiome to repair
  • might impair the absorption of many key nutrients in the short and intermediate-term
  • increased susceptibility to infection after using antibiotics. 

That isn’t to say they should never be given, but there is a much bigger, growing problem, antibiotic or multidrug-resistant bacteria. This represents a grave risk as an ever-growing number of antibiotics become less effective.

This is not in the best interest of us or our cats and dogs, and the current trajectory cannot be allowed to continue unabated.

I won’t say every relevant agency or organization, but I will say most, human and animal, are well aware of the problem. While organizationally, it is understood that action needs to be taken that hasn’t filtered down to the individual veterinarian or health care provider.

One of if not the most significant contributing factors is the overuse of antibiotics.

The AVIM has a position paper on the overuse of antibiotics. Various vet specialty colleges have guidelines for the use of antibiotics for various health conditions, but this has had minimal effect on the actual prescribing practices of many, if not most primary care veterinarians.

Overprescribed

In a 2016 study, researchers in the UK found that,

“Overall, 25 percent of 963,463 dogs and 21 percent of 594,812 cats seen at veterinary practices received at least one AM over a two-year period (2012–2014), and 42 percent of these animals were given repeated AMs.” (Buckland, 2016)

In a study at the University of Minnesota teaching hospital, they found that,

“Overall, 249 (29.1%, 95% confidence interval [CI] 26.1%-32.1%) cats and dogs were administered at least 1 antibiotic.” (Hsieh, 2019)

While that only tells us how many were prescribed, it doesn’t tell us if the antibiotics were overprescribed.

“Overall, 48.4% (125/258) of antibiotics administered or pre­scribed to dogs, and 36.5% (19/52) to cats, had no clinical evidence of infection recorded in the medical record on the study dates.” (Hsieh, 2019)

Furthermore, only 22.9 % of the dogs and cats prescribed an antibiotic underwent culture and susceptibility testing.

While most were given first-tier antibiotics, there were also many incidences of antibiotics, such as Enrofloxacin (which can have more severe side effects) and third-generation cephalosporins (High Importance). Yet, these were given to some dogs and cats that did not have confirmed infections. 

Worse, the use of cephalosporins at this teaching hospital was explicitly discouraged. Furthermore, this is a hospital filled with veterinary specialists. Who are likely much more aware of the guidelines for prescribing antibiotics and antibiotic stewardship.  This means that it is not representative of most primary care veterinary clinics.

A 2015 survey conducted by the AVMA found that 88% of veterinarians were unaware of the existence of antibiotic use guidelines. While it was a relatively small sample size, the results are still concerning. Hopefully, that number has dropped significantly since then. (AVMA)

In a study published this year, the researchers presented several common medical scenarios to veterinarians. The vets were invited to participate via email by their state’s public health veterinarian. A majority of the veterinarian surveyed were general practitioners, while some were specialists or worked at emergency clinics.

The results showed that even veterinarians that were aware of the guidelines are still likely overprescribing antibiotics in certain situations.

On the bright side, around 60% of respondents reported being aware of the various guidelines for health conditions.  

While awareness of the antibiotic guidelines resulted in a statistically significant decrease in their use, many were still overprescribing antibiotics. (Taylor, 2022)

While 90% of the vets indicated they would conduct diagnostic tests for acute diarrhea, those tests were often to rule out other causes, not to confirm a bacterial infection. 

Only around 60% of the vets, however, indicated they would do skin tests on the itchy dog with skin lesions to see if an antibiotic is necessary.

The table below shows the response rates for the health conditions.

It’s possible, if not probable, that the survey underrepresented the level of overprescription as there was no time limit, but more importantly, there was no owner, sick dog, or cat to pull on the vet’s heartstrings. 

The veterinarians were also invited to participate in the survey resulting in a non-random sample, so the respondents may have had a greater interest or understanding of antibiotic stewardship.

Buttressing that argument would be the massive shift from 22% of vets being aware of the guidelines in the survey from 2015 to 60% in 2022. 

Yes aware of the guidelines Not aware of guidelines
Feline Urinary Tract Infection 1267(60.4%) 831(39.6%)
Antibiotics Prescribed 558 (44%) 452(54.4%)
No Antibiotics 709 (55.6%) 379(45.6%)
Canine Skin Infection 1226(60%) 817(40%)
Antibiotics Prescribed 1003(81.8%) 695(85.1%)
No Antibiotics 223(18.2%) 122(14.9%)
Feline Upper Respiratory 1254(60.2%) 829(40%)
Antibiotics Prescribed 300(23.9%) 276(33.3%)
No Antibiotics 954(76.1%) 553(66.7%)
Canine Diarrhea  1249(60.1%) 829(39.9%)
Antibiotics Prescribed 663(53.1%) 491(59.2%)
No Antibiotics 586(46.9%) 338(40.8%)
Canine Dental 1119(59.8%) 753(40.2%)
Antibiotics Prescribed 380(34%) 273(36.3%)
No Antibiotics 739(66%) 480(63.7%)

These studies demonstrate that antibiotics are likely overprescribed in veterinary medicine, similar to that found in human medicine. Meaning if your dog or cat was prescribed antibiotics, there is a good chance that they didn’t actually need them.

Currently, many patients are sent home with antibiotics even when they aren’t necessary or Indicated based on the symptoms.

A patient will sometimes be sent home with broad-range antibiotics before they even know which antibiotics the infection might be susceptible to.

The overuse of antibiotics has undoubtedly been a significant contributing factor in the increase of antibiotic-resistant bacteria. 

The rise in antibiotic-resistant bacteria has necessitated the use of even more potent antibiotics, which can often carry with them significantly stronger side effects. Even if the side effects are relatively uncommon. However, dealing with the potential side effects might be the only option in some situations.

New Antibiotics?

Antibiotic resistance wouldn’t be as much of a problem if there were many more in development to replace the antibiotics that have become less effective. That, however, isn’t the case.

This is largely because pharmaceutical companies have prioritized research for more profitable drugs, as antibiotics may only be given for a couple of weeks. Many companies have even discontinued R&D entirely. 

This is in spite of the numerous strong financial incentives(essentially begging) developed and implemented during the Obama Administration back in 2014.

While Covid-19 pushed antibiotic-resistant bacteria to the back burner of everyone’s attention, it is still very much an ongoing threat.

Antibiotic and Antibiotic Resistance: The Tragedy of the Commons

One major problem is that everyone wants to blame someone else for the emergence and proliferation of antibiotic-resistant bacteria. I’m not overprescribing antibiotics; It’s other Veterinarians and healthcare providers overprescribing. It is the fault of the production animal vets. It’s because farms were using growth-promoting antibiotics until relatively recently 2017. 

Antibiotics suffer from the Tragedy of the Commons, Where everyone is incentivized to skirt the guidelines.

In fact, everyone’s dominant choice is to continue to over-prescribe and use broad antibiotics instead of narrow antibiotics. The dominant choice is to prescribe antibiotics prophylactically instead of waiting for them to be necessary.

Because Vets, Healthcare Providers, and patients are all ultimately incentivized as individual practitioners to continue on the current trajectory. 

As a pet parents or as a patient, we want the issue to be resolved as quickly as possible. This is why many vets and Healthcare providers send patients home with a broad antibiotic, sometimes even a cocktail, before they have the culture back to know which antibiotics to prescribe. 

Both Vets and doctors are extremely busy, so it’s easier and faster to just send you home with a broad antibiotic or cocktail and hope it works instead of waiting a couple of days.

Antibiotics are also often prescribed as a preventative measure. Thus reducing the risk of having another appointment. However, with telemedicine, this should be less of an issue. 

We are all guilty of being impatient at times and probably aren’t going to be happy to wait for a couple of days to see which specific antibiotics work, especially when you might decide to just go to the doctor or vet down the road.

Antibacterial Soap and Shampoo

Antibacterial is a marketing buzzword.

However, for antibacterial soap to actually be effective, it has to sit for 2 minutes. Most people aren’t washing their hands for two minutes.

Furthermore, most of the research suggests that soap and water are just as effective. Most of the time, There is no need to use antibacterial soap. 

What This means for our pets is that Most of the time, there is no need for antibacterial shampoo. However, based on the best sellers on Amazon (1 and 3) and Chewy’s (2, 4, 6, and 7), they are most assuredly both overused and not used correctly by the public.

Triclosan and 18 other ingredients in Antibacterial soaps were banned in OTC antibacterial soaps not too long ago. Due to a number of factors related to long-term safety and effectiveness. 

This has not yet fully filtered down to companion animals.

While some argue that Antibacterial soap hasn’t been a contributing factor, it is probably better to err on the side of caution given the current situation. As some research does show, it may have an impact.

What this means is you can probably skip the antibacterial shampoo unless your veterinarian specifically told you to use an antibacterial shampoo.

What you can do?

Next time your vet or healthcare provider wants to prescribe antibiotics, ask them.

Is there a test that can confirm the need for antibiotics?

Is it entirely necessary to start now, or can it wait until the results come back showing susceptibility to a narrow antibiotic? Instead of just prescribing one and hoping it’s the right antibiotic.

Is the antibiotic being prescribed prophylactically? If so, what signs can I be on the look for before proceeding to give antibiotics?

The great part about asking these questions is that it takes you and the veterinarian out of what Daniel Kahneman describes in Thinking Fast and Slow as System 1 (fast, instinctive emotional) thinking into System 2 (slow, deliberate, logical). It forces the veterinarian to slow down and think instead of simply going with the relatively common default response of prescribing antibiotics.

This also involves the understanding that you might leave the vet’s office without medication the same day. 

It may mean going back to pick up a prescription a couple or several days later if there is an infection or after the susceptibility results come back.

This is probably another contributing factor to why Antibiotics are overprescribed because the vet doesn’t want to deal with an angry client asking why they didn’t prescribe antibiotics in the first place.

The decision to prescribe antibiotics is not entirely benign as they can have a profound impact on the gut microbiome, and given how important a healthy gut microbiome is for the health of both our companion animals and us, we should already be more cautious in the decision to take or prescribe antibiotics.

This means patients and pet parents also have an essential role to play. Because without buy-in and understanding from patients and pet parents, there will always be veterinarians or healthcare providers that will feel forced to prescribe an antibiotic.

One of the other most important things that patients and pet parents can do is to make sure you are following through with the prescription fully, even if the clinical signs appear to be resolved, as you don’t want to potentially start all over again with a more potent antibiotic.

Conclusion

While there are other things that need to happen, such as 

  • rapid susceptibility testing, 
  • further development of guidelines for antibiotic use (especially for diarrhea which is often self-correcting)
  • ensuring the guidelines are understood and put to use by Veterinarians
  • New Antibiotics
  • And many more

Ultimately Slowing and hopefully reversing the trend of antibiotic-resistant bacteria requires everyone, both doctors and patients, to be more judicious in the use of antibiotics.

Because if we don’t, what was previously a simple bacterial infection, could become the Sword of Damocles, and that will have wide-ranging consequences.

Consensus Statements and Guidelines

ACVIM Consensus Statement on Therapeutic Antimicrobial Use in Animals and Antimicrobial Resistance

Recommendations for approaches to meticillin-resistant staphylococcal infections of small animals: diagnosis, therapeutic considerations and preventative measures

Diagnosis and treatment of dermatophytosis in dogs and cats

Diagnosis and treatment of demodicosis in dogs and cats

Guidelines for the diagnosis and antimicrobial therapy of canine superficial bacterial folliculitis (Antimicrobial Guidelines Working Group of the International Society for Companion Animal Infectious Diseases)

International Society for Companion Animal Infectious Diseases (ISCAID) guidelines for the diagnosis and management of bacterial urinary tract infections in dogs and cats

Antimicrobial use guidelines for treatment of respiratory tract disease in dogs and cats: Antimicrobial Guidelines Working Group of the International Society for Companion Animal Infectious Diseases

2019 AAHA dental care guidelines for dogs and cats

Works Referenced

AVMA. Understanding companion animal practitioners’ attitudes toward antimicrobial stewardship. J Am Vet Med Assoc. (2015) 247:883–4. https://doi:10.2460/javma.247.8.883

Buckland, E.L., O’Neill, D., Summers, J., Mateus, A., Church, D., Redmond, L. and Brodbelt, D. (2016), Characterisation of antimicrobial usage in cats and dogs attending UK primary care companion animal veterinary practices. Veterinary Record, 179: 489-489. https://doi.org/10.1136/vr.103830 

Hsieh, ES, Bollig, ER, Beaudoin, AL, Morrow, A, Granick, JL. Serial point-prevalence surveys to estimate antibiotic use in a small animal veterinary teaching hospital, November 2018 to October 2019. J Vet Intern Med. 2022; 36( 1): 244- 252. https://doi:10.1111/jvim.16314

Taylor, D. D., Martin, J. N., & Scallan Walter, E. J. (2022). Survey of companion animal veterinarians’ antimicrobial drug prescription practices and awareness of antimicrobial drug use guidelines in the United States. Zoonoses and Public Health, 69, 277– 285. https://doi.org/10.1111/zph.12915