Plague in Pets

Plague in pets, does it still exist, and can it affect your dog or cat. ? The answer is yes, and according to the World Health Organization there are still thousands of reported cases of plague in humans every year.

In the United States, plaque can still attack both your dog or cat and this beast is primarily located in California as well several Southwestern states. It is very real, it does exist, and although quite rare, it can be passed from pets to humans. It also haunts other parts of the world, especially Asian countries.

The plague is a bacterial infection that is caused by Yersinia pestis, which is transmitted by rodents.

This infection is a rod shaped bacterium and takes on three different forms of the plague; Pneumonic, Septicemic, and the very infamous Bubonic Plague that literally killed one third of Europe’s population in the 1300s.

What is interesting about history is that during this time almost every cat was killed because it was thought that cats spread this infection. Nothing was further from the truth.

How it is transmitted:

The bacterium itself does not infect your dog or cat. But like most bacterium, it is transmitted by either mites or fleas. With the plague, it is a rodent flea called Xenopsylla cheopis. This flea is found on rats, prairie dogs, squirrels, rabbits, wild mice, but more importantly, both dogs and cats. But none of these animals cause the plague, infected fleas do.

Your pet will become infected when they have been bitten by this flea or by eating the body parts of another animal or rodent that has been infected. What is still very scaring about this disease is that the flea can carry the infection for several months before it dissipates.

This flea can also infect humans, although very rare. However, humans can get the plague by direct contact with the tissues or body fluids from a plague infested animal or by inhaling airborne droplets. In airborne transmission, humans can only catch the pneumonia form, which is not real serious.


Because there are three different types of the plague, there will be different symptoms.

Bubonic plaque will affect your pet’s lymph nodes surrounding the place where they were actually bitten, causing them to become dangerously enlarged and painful. Cats may also suffer from severe blood infections, followed by fevers, chills, and than shock if severe enough.

The Septicemic form of plague enters into your pet’s bloodstream and infects several organs of their body, while the pneumonic form will affect the lungs.

Dogs have a much stronger natural immunity to the plaque, and thus the symptoms may not be as severe as in cats. They will generally only develop swollen nymph nodes. Cats, however, have a much weaken immune system to this disease, and will in most all cases suffer from all the symptoms.

With severe infection, the survival rate of the plaque is only about fifty percent in cats.

Diagnoses and treatment:

Plague in pets, unlike other bacteria infections, is fairly easy to detect. Your veterinarian will run cultures on various tissue samples or blood testing. They will normally take two tests, about three weeks apart, to look for changes and abnormalities in antibody levels.

If your pet is diagnosed with the plague, it must immediately be reported to the local, state, and federal health departments.

If detected in time, especially critical for cats, it can be treated with antibiotics such as tetracycline or doxycydine for a period of at least three weeks, depending on how severe it is. There is a human vaccine for the plague, but there is no vaccine for either dogs or cats.


The best methods for preventing this age old and potentially fatal infection are to keep your pets away from rodents if at all possible, especially if you live in California or the Southwest.

Do what ever you can to keep rodents away from your house, your barn, or open areas.

Both dogs and cats are natural hunters. Try not to let your cats roam in these areas if possible. Walk with your dog and watch them closely. Providing your pet the best defense you can give them against fleas is the next step toward prevention, and there are several very good flea collars and repellents available.

However, there is one more thing you can do for your pet.

Give them Vitamin B1, Thiamine. Fleas of any kind absolutely hate the taste of thiamin in your pets’ blood. It is perhaps the best thing you could do for them; it is a very effective as well as very inexpensive.