New Kitten 101, Part 2: Kitten Vaccines

Congratulations on your new kitten! We hope you’re getting acquainted and loving her. In the second of our two-part blog series, we’re reviewing all things kitten vaccines—what and when to get, and why. Check out our first part, which provides an overview living arrangements, deworming and parasite prevention, spaying and neutering suggestions, and diet recommendations.

What Are Vaccinations?

Vaccines are an important tool to protect your kitten from transmissible and, in some cases, very serious diseases. Vaccines are made up of tiny, inactive pieces of disease-causing organisms (pathogens, like viruses and bacteria). These inactive pieces stimulate your kitten’s immune system to produce antibodies.

Antibodies are small molecules that recognize and attach to pathogens and mark them for the body’s white blood cells to destroy. Vaccination allows your kitten’s immune system to prime itself, so that if your kitten is ever exposed to one of these diseases, her body will be able to fight it off.

R Is for Rabies

Rabies is a serious disease with 100% fatality if left untreated. The rabies virus can be carried and transmitted by any mammal species, including people! The rabies virus is most commonly transmitted from the bite of an infected animal. It makes its way into the nervous system and eventually travels to the brain, where it causes the classic signs of aggression and foaming at the mouth.

Domestic animals that are up to date on their vaccination but have been exposed to rabies simply need a booster vaccine. And, they should be monitored for 45 days for signs of rabies.

Domestic animals that have not been vaccinated, or are not current on their rabies vaccine, are evaluated on case-by-case basis. In some instances, however, state law requires the animal to be euthanized. The Centers for Disease Control and Prevention (CDC) is a great resource for additional information about rabies and the steps taken if an exposure happens.

Kittens receive their first rabies vaccine at 12–16 weeks of age and then annually thereafter. Since one of the main sources of rabies in the state of Washington is the bat population, it is important for all cats, even indoor-only cats, to stay up to date on their rabies vaccines.

Rabies exposure to humans is very serious. The CDC offers important information about what to do if you have been infected.

V Is for Viruses

Kittens are at risk for a handful of viruses, including Feline Viral Rhinotracheitis (FVRCP), which also is known as the herpes virus; Calici virus; and Panluekopenia virus. These viruses most commonly cause upper respiratory signs in cats—sneezing, congestion, and runny eyes and nose are most frequently seen.

FVRCP and Calici work similarly to the human herpes virus; once a cat contracts it, the virus will stay in her body forever, only coming during times of stress or illness. In people, the herpes virus commonly causes cold sores; in cats, it causes upper respiratory illness (URI).

Panleukopenia is closely related to the Parvovirus in dogs, although it sometimes goes by the misnomer “Feline Distemper.” Merck Manuals offers a detailed overview of the virus. Young cats and kittens are most susceptible to Panleukopenia; older cats often have subclinical infection, meaning they show no signs of the disease but can still spread the virus. For young cats that are infected, vomiting, diarrhea, depression, dehydration, and death can occur. Pregnant cats infected with the virus can pass it their kittens, where it affects the developing brain, causing these kittens to be unable to walk normally when they are born. Otherwise, the kittens are fine, as YouTube sensation Charley illustrates.

Healthy kittens born to healthy mothers receive antibodies to FVRCP, Calici, and Panleukopenis viruses in their mother’s milk. When a kitten is vaccinated, the maternal antibodies can actually interfere with the kitten’s own antibodies that her body begins to produce. Because the maternal antibodies last until about 16 weeks of age, we recommend a series of vaccinations for FVRCP so that we can be sure the kitten has developed a full complement of her own antibodies.

Kittens should receive their first FVRCP vaccine at 6–8 weeks of age and then every 3–4 weeks until they are at least 16 weeks old. After the initial series, the vaccine is good for one year. And after the first year, the vaccine is then good for three years.

F Is for Feline Leukemia

The feline leukemia virus (FeLV) attacks the white blood cells of the body’s immune system, eventually leaving the body susceptible to infection by other viruses and bacteria.

All cats infected with FeLV will go through a period where the virus is in their bloodstream and they are actively shedding the virus in their urine, feces, and saliva. Some cats are able to clear the virus from their systems after this initial phase, but others cannot clear and the virus persists in their bone marrow. At this time, we have no way of predicting which cats will be able to clear the virus and which will become persistent carriers.

Cats most commonly transmit FeLV in their saliva via grooming or fighting with other cats. Therefore, any cat who will be venturing outdoors must be kept up to date on their FeLV vaccine. Even indoor-only cats can escape through open windows or doors, or out of their carrier when traveling, and can risk exposure.

Kittens receive their first FeLV vaccine at 12–16 weeks of age and a booster 3–4 weeks later. After the initial series, the vaccine is good for one year.

For more detailed reading on FeLV, we recommend Cornell University’s College of Veterinary Medicine site.