The 5 Most Common Kitten Illnesses

By Jennifer Coates, DVM

Ideally when you adopt a new kitten, the kitten will be healthy and without any medical issues. However, that’s not always the case. Kind-hearted people often take in obviously sick kittens with the intent of nursing them back to health. In other cases, kittens will initially appear to be in good shape but then develop health problems within days or weeks of arriving in their new home.

There are a few problems that occur with relative frequency in young kittens. Knowing what they are will help you plan for the future. Here are five kitten conditions that veterinarians commonly see in their practices.

1. Upper respiratory infections are one of the most common illnesses veterinarians diagnose in young kittens. Characterized by sneezing, runny eyes, runny nose, lack of appetite, and lethargy, upper respiratory infections are extremely contagious and easily passed from one kitten to another. Adult cats may be infected as well, particularly if they are stressed or housed in close contact with one another, but the symptoms are generally most severe in kittens.

Many kittens will recover from an upper respiratory infection within a week or two with good nursing care (rest, encouraging them to eat and drink, wiping discharge from their eyes and nose with a warm damp cloth, etc.). But, if your kitten stops eating or her symptoms fail to improve, make an appointment with your veterinarian.

2. Ear mites are also extremely common in kittens, though cats of any age can be infected. These parasites are contagious to other cats and less frequently to dogs. The most common sign of an ear mite infestation is a black/brown discharge in the ears that appears similar to coffee grounds. The kitten’s ears are usually itchy as well, and there may be sores and inflammation around the head and neck if the kitten has been scratching.

Over-the-counter ear mite treatments are available and work if you closely follow the directions, but your veterinarian can run a simple test to confirm that mites (and not yeast or bacteria) are responsible for your kitten’s symptoms and prescribe medications that will eliminate the mites with just one application. To eradicate ear mites from your home, make sure that all pets receive treatment.

3. Intestinal parasites are common enough in kittens to warrant routine fecal examinations and dewormings. Roundworms and hookworms are the most frequently seen intestinal parasites, and many kittens pick up these worms soon after birth, either through their mother’s milk or through contact with contaminated environments. Other parasites such as tapeworms, Coccidia, and Giardia may also be seen.

To diagnose intestinal worms, your veterinarian will examine a sample of your kitten’s feces under the microscope and then prescribe a deworming medication that will kill the specific type of parasite that your kitten has. Make sure to closely follow the instructions on the medication since multiple doses of dewormer are often necessary.

4. Fleas are not an uncommon finding in kittens either. Naturally, fleas can infest cats of all ages, but flea infestations can be particularly troublesome for young kittens. Because of their small size, tiny kittens heavily infested with fleas may become anemic due to blood loss from flea feeding. Fleas can also spread diseases to infested kittens, including Bartonella and Mycoplasma infections.

Getting rid of fleas involves the regular (often monthly) use of a flea medication that is approved for use in kittens, treating all other susceptible pets in the household, and environmental controls (vacuuming rugs, upholstery, and floors, laundering pet and human bedding, etc.). Your veterinarian can recommend the safest and most effective type of flea prevention based on your kitten’s needs.

5. Diarrhea can have many causes. In some cases, stress associated with major changes in a kitten’s life contributes to the development of diarrhea. Being separated from mother and littermates, moving to a new home, and meeting new people are all stressful for kittens, though they are a necessary part of kittenhood. In addition, a change in diet can cause diarrhea. When diarrhea is caused by these types of factors, it will generally be short-lived and respond to symptomatic treatment (returning to the previous diet, stress-relief, and probiotic supplements).

However, diarrhea can also be a sign of serious illness in kittens. Intestinal parasites, bacterial and viral infections, immune disorders, and more can all be to blame. Because kittens are not able to withstand the effects of diarrhea very well, it is always best to have your kitten evaluated by a veterinarian when the diarrhea is especially severe or persists for more than a day or two.

This is obviously not an exhaustive list of all of the potential health issues that kittens can face. Veterinarians might not see Feline Infectious Peritonitis (FIP) frequently in their practices, but this is a serious disease and almost always fatal when diagnosed. Feline Leukemia Virus (FELV) and Feline Immunodeficiency Virus (FIV) are relatively common viral infections that can cause severe illness and death in some cats. Your veterinarian can run tests for FELV and FIV, and if your kitten is infected, design a management plan that will keep your kitten happy and healthy for as long as possible. Feline Panleukopenia was once commonly diagnosed in kittens. However, with the advent of vaccinations against this disease, veterinarians don’t see it nearly as often anymore. Still, it’s a disease that does arise, especially in young, unvaccinated kittens. Symptoms include diarrhea, vomiting, lack of appetite, lethargy, and dehydration. Panleukopenia is often fatal, even with treatment.

All newly adopted kittens should be seen by a veterinarian within a day or two of coming home. The doctor will perform a physical exam and possibly run some diagnostic tests, treat any problems that are found, and put together a plan for vaccinations, deworming, diet, and other preventive care measures that will hopefully keep your cat healthy for years to come.

Editor's Note: Portions of this article were adapted from a blog post by Dr. Lorie Huston.