Should the lepto vaccine be required for all dogs?  

According to the just released 2022 AAHA Canine Vaccination Guidelines, it depends. 

Unless there is a specific medical reason not to vaccinate, these five core vaccines are recommended for all dogs, regardless of lifestyle or geography: distemper, adenovirus, parvovirus, parainfluenza, and rabies.  

But other vaccines—such as leptospira, Lyme disease, Bordetella, and canine influenza—could be considered core (recommended for all canine patients) if you live in a region where pathogens have reached endemic levels, or when a dog’s lifestyle and surroundings pose extra risks—as with the Western diamondback rattlesnake toxoid.  

The guidelines state: “These traditionally noncore vaccines may be considered a core vaccine by veterinary practices in those locations.” 

“In the 2022 guidelines, we’ve provided veterinarians with a blueprint for developing vaccine protocols that address individualized risk and ensure that all dogs, no matter their lifestyle, are protected from disease, and that herd immunity is maintained,” said John Ellis, DVM, PhD, DACVP, DACVM, co-chair of the 2022 AAHA Canine Vaccination Guidelines Task Force. 

“Vaccines are an essential part of preventive canine healthcare for both individuals and populations,” Ellis said. “They also provide an important barrier to some infectious agents that can pass from dogs to humans.”  

To help in the planning and creation of personalized plans, the guidelines include a comprehensive table listing canine core and noncore vaccines, with the recommended vaccination and revaccination schedule for each.  

“When in doubt, vaccinate.” 

Some dog owners may believe their dogs don’t need vaccinations, but this can be a dangerous misconception. The guidelines point to repeated canine distemper and parvovirus outbreaks in shelters—as well as recent measles outbreaks in human populations—as evidence that low vaccination rates can have public health consequences.  

The guidelines state: “Licensed canine vaccines have a high degree of proven safety and efficacy” and “veterinarians can assume that the benefits of vaccination far outweigh the risks in cases of dogs with unknown immune status or vaccination history.”   

“While individual dogs with low-risk lifestyles (i.e., minimal exposure to other animals) may benefit from herd immunity, unvaccinated individuals are still more vulnerable to infection, and reductions in population-level vaccination rates without eradication of the pathogen will inevitably result in a recurrence of disease at outbreak levels,” according to the guidelines. 

A medical success story—and ongoing risks 

Rabies used to run rampant in the United States—but stray dog control programs introduced in the 1940s and routine rabies vaccination for owned dogs eliminated the canine rabies virus variant from circulation by 2008. That doesn’t mean there aren’t still risks. 

Today, dogs (and humans) in the United States and Canada remain at risk from host-adapted rabies variants in wildlife reservoir species such as skunks, raccoons, foxes, and bats. The guidelines say spillover to dogs is most common in areas with racoon variants, less common in areas with skunk variants, and least common in areas with only the bat variant of the rabies virus. 

Vaccination of companion animals protects the health of individual pets; improves animal welfare in shelters; protects the public health; and reduces the occurrence of infectious diseases that transmit mainly within a species, such as distemper, parvovirus, and the canine variants of the rabies virus, say the guidelines.  

The document states: “Vaccines are one of the medical and public health successes of the 19th and 20th centuries. Their use has reduced morbidity and mortality more than any other intervention in human and veterinary medicine.” 

Because these conditions are constantly in flux, the guidelines suggest using resources like the US Centers for Disease Control and Prevention (CDC)’s annual rabies surveillance summary with maps of terrestrial rabies variant distribution and spillover events into dogs. The Canadian Food Inspection Agency (CFIA) provides Canadian rabies statistics. 

Local and state health departments are the best place to start for specific regulations on which vaccinations are required in your area.  

No vaccine is 100% effective 

The guidelines warn that it’s not enough to have vaccines: They must be used and stored according to the manufacturer’s instructions—and even then, immunity isn’t a guarantee. 

“Vaccination failures, namely, the occurrence of disease in an animal that has received an appropriately administered vaccine against that disease, are rare but should be expected because no vaccine achieves 100% effectiveness,” say the guidelines. 

Some reasons a vaccine might not be effective include: 

• Failure of the vaccinated patient to mount an adequate immune response 
• Exposure to the infection before being fully vaccinated 
• Interference of maternal antibodies 
• Improper storage or handling of vaccine, including inappropriate administration 

• Waning immunity (e.g., immunosenescence, or age-related deterioration of the immune system) 
• Vaccine manufacturing errors, such as lack of potency due to instability, expiration, or improper storage 

Vaccination failures should be promptly reported to the manufacturer and/or to the United States Food and Drug Administration (USDA). 

Empowering veterinarians 

AAHA Chief Medical Officer Jessica Vogelsang, DVM, said: “We’re so proud of these updated guidelines because they help veterinarians take charge of their patients’ health based on real-time data about risks in their area and the dogs’ lifestyles. This is especially important as we’re seeing increased reports of leptospirosis. These guidelines empower veterinary teams to be flexible and responsive to new developments as they determine which vaccines should be made ‘core’ for their patients.” 

So, is the lepto vaccine ‘core for you’?  

With the help of the 2022 AAHA Canine Vaccination Guidelines, that’s up to the veterinary team to decide. 

For more on the guidelines and related resources, including a vaccine lifestyle calculator, FAQs, and client communication tools, visit aaha.org/canine-vaccinations. 

The 2022 AAHA Canine Vaccination Guidelines are generously supported by Boehringer Ingelheim Animal Health, Merck Animal Health, Zoetis, and Elanco Animal Health.