Many pet owners wonder if “cat flu,” an illness affecting felines, can spread to humans. The primary viruses causing “cat flu” in cats are Feline Herpesvirus (FHV-1) and Feline Calicivirus (FCV). These viruses are species-specific, meaning they infect only cats and generally do not pose a risk to human health. While “cat flu” itself is not a human concern, cats can transmit other distinct diseases to people.
Understanding Feline “Cat Flu”
“Cat flu” is a common term for an upper respiratory infection that affects cats, often resembling a common cold or flu in humans. The primary causes of this highly contagious condition are Feline Herpesvirus type 1 (FHV-1) and Feline Calicivirus (FCV).
Typical signs of “cat flu” in cats include sneezing, discharge from the nose and eyes, and lethargy. Cats may also develop mouth ulcers and may experience a fever or loss of appetite. The infection spreads easily among cats through direct contact, airborne droplets, and shared items like food bowls or bedding.
Why Feline Flu Viruses Don’t Affect Humans
Feline Herpesvirus and Feline Calicivirus do not infect humans due to their high degree of species specificity. These viruses have evolved to recognize and bind only to specific receptor molecules found on the surface of cat cells. Without these compatible receptors, the viruses cannot effectively attach to, enter, or replicate within human cells.
The genetic makeup and structural components of FHV-1 and FCV are uniquely adapted to the biological environment within cats. The risk of human infection from these specific feline viruses is considered negligible.
Other Diseases Cats Can Transmit to Humans
While “cat flu” viruses are species-specific, several other diseases, known as zoonotic diseases, can be transmitted from cats to humans.
Toxoplasmosis
This parasitic infection is caused by Toxoplasma gondii, which reproduces in the intestinal tracts of cats. Humans can contract it by accidentally ingesting the parasite from contaminated cat feces, often through cleaning litter boxes, or by eating undercooked meat. Most infected individuals show no symptoms, but it can be severe for pregnant women or those with weakened immune systems.
Ringworm
This fungal infection affects the skin, hair, and nails, appearing as scaly, circular patches. It can be transmitted to humans through direct contact with an infected cat or contaminated surfaces. Kittens and long-haired cats are particularly susceptible to ringworm.
Cat Scratch Disease (CSD)
Caused by the bacterium Bartonella henselae, which cats carry, often without showing symptoms themselves. Transmission to humans typically occurs through a scratch or bite from an infected cat. Symptoms can include a rash or bumps at the site of injury, swollen lymph nodes, and fever.
Rabies
A fatal viral disease that affects the nervous system and is transmitted through the saliva of an infected animal, usually via a bite. While less common in domestic cats, especially vaccinated ones, cats are the most frequently reported rabid domestic animal in the United States. Vaccination is a primary preventative measure.
Protecting Yourself and Your Cat
Implementing good hygiene practices is important for minimizing the risk of transmitting zoonotic diseases from cats. Regular handwashing with soap and water after handling your cat, cleaning litter boxes, or touching potentially contaminated surfaces is a simple yet effective step. Litter boxes should be cleaned daily, as the Toxoplasma parasite takes at least 24 hours to become infectious after being shed.
Responsible pet care also plays a significant role in protecting both human and feline health. This includes scheduling regular veterinary check-ups for your cat, which allows for early detection and treatment of potential health issues. Ensuring your cat receives recommended vaccinations, such as for rabies, and consistent parasite control (fleas, ticks, worms) reduces disease transmission risks. Feeding a balanced diet and keeping cats indoors can also limit their exposure to pathogens.