Farm Animals and Pets Also Need Vaccines

June 30, 2019 Rene F. Najera


A new triple vaccine for pigs just went to market. It offers protection against Erysipelas (a bacterial infection caused by Erysipelothrix rhusiopathiae), Leptospirosis (a bacterial infection) and Parvovirus (a viral infection). All three of these infections can cause stillbirth in pigs, so farmers are encouraged to use the vaccine to increase the size and health of their herds.

Vaccines for animal diseases are nothing new. In 1879, Louis Pasteur developed a vaccine against chicken cholera (a bacterial infection caused by Pasteurella multocida). The discovery was accidental, by the way:

“Pasteur attenuated, or weakened, the bacteria for use in the vaccine. He happened upon the method of attenuation by accident: in his lab, he was studying fowl cholera by injecting chickens with the live bacteria and recording the fatal progression of the illness. He had instructed an assistant to inject the chickens with a fresh culture of the bacteria before a holiday. The assistant, however, forgot. When the assistant returned a month later, he carried out Pasteur’s wishes. The chickens, while showing mild signs of the disease, survived. When they were healthy again, Pasteur injected them with fresh bacteria. The chickens did not become ill. Pasteur eventually reasoned the factor that made the bacteria less deadly was exposure to oxygen.”

Today, veterinary associations recommend vaccination for animals, especially domesticated animals like dogs and cats that are in constant contact with humans. This is because some diseases, when passed on to humans, can be quite deadly. For example, rabies is 100% fatal if the person who receives a bite from a rabid animal is not given the rabies vaccine as soon as possible. While rare in the United States, rabies kills tens of thousands of people around the world. In India alone, the number of people bitten by dogs each year is estimated to be in the millions, and the number of people dying from rabies is estimated to be around 20,000.

The concept of One Health (animal health has impacts to human health, and vice versa) is something that is being included in more and more public health and veterinary health policies, including vaccination. Unfortunately, just like with human vaccines, animal vaccines are being refused by pet owners more and more. In the United Kingdom, about 25%  of dogs and 35% of cats are reported by their owners as not vaccinated or under-vaccinated. Although rabies is eliminated in the UK, other vaccine-preventable diseases in animals are still circulating there.

Time will tell if diseases that can threaten the lives of pets and other animals are allowed to return like measles in humans has. Allowing vaccine-preventable diseases to decimate food animals like pork, chickens and beef would not only be a severe hit to the economy. It would threaten food security for people all around the world as these animals are a source of protein in the diets of many and a source of income for those who raise them and take them to market.