When a cat begins to sneeze or develops a runny nose, it is natural for caregivers to worry about their own health due to the close contact shared in the home environment. This concern stems from the fact that various organisms, including viruses and bacteria, can cause similar respiratory symptoms in both people and pets. Understanding the biological mechanisms of these illnesses helps determine if a feline’s sniffles pose a threat to the people around it.
Can Human and Feline Cold Viruses Cross Species
The possibility of a cat transmitting a “cold” to a person is generally negated by host specificity. Viruses are highly specialized agents that must bind to specific receptor proteins on the surface of host cells to successfully invade and replicate. The viruses that cause the common cold in humans, primarily Rhinovirus, are adapted to interact with receptors found on primate cells, making them ineffective against feline cells.
The respiratory viruses that affect cats, such as Feline Herpesvirus-1 (FHV-1) and Feline Calicivirus (FCV), are similarly species-specific. These pathogens have evolved exclusively to target and infect cells found within the feline anatomy. They do not possess the necessary biological “keys” to unlock human cells. Therefore, direct transmission of a true feline cold virus to a human is not considered a risk.
This biological barrier usually prevents human cold viruses from infecting cats as well. However, rare exceptions exist in the study of “reverse zoonosis,” where a human illness can pass to an animal. Certain strains of Influenza A and norovirus, for example, have demonstrated the ability to infect cats under specific conditions. These instances are distinct from the typical human cold, which is caused by a family of viruses largely confined to human hosts.
What Causes the Common Cold in Cats
When a cat exhibits cold-like symptoms, the veterinarian usually diagnoses a Feline Upper Respiratory Infection (FURI). The majority of FURI cases are caused by two primary viral agents: Feline Herpesvirus-1 (FHV-1) and Feline Calicivirus (FCV). Both viruses are highly contagious among felines, spreading through direct contact with nasal, ocular, or oral secretions, or via contaminated objects.
FHV-1, which causes Feline Viral Rhinotracheitis, is often associated with severe inflammation of the eyes and nose. Once infected, the virus remains dormant within the cat’s body for life, often reactivating during periods of stress or illness. This latency means the cat can become a chronic carrier, potentially shedding the virus throughout its life.
Feline Calicivirus (FCV) tends to affect the oral cavity and lungs, frequently resulting in painful ulcers on the tongue, palate, or gums. A cat infected with FCV may continue to shed the virus continuously for months or years, posing a persistent risk to other cats in the household.
FURI can also be complicated by secondary bacterial infections, such as those involving Bordetella bronchiseptica or Chlamydophila felis. These bacteria capitalize on the damaged respiratory lining caused by the initial viral infection. This often leads to a change in nasal discharge from clear to thick and purulent.
Recognizing Symptoms and When to Seek Veterinary Care
The symptoms of Feline Upper Respiratory Infection closely mirror a human cold. These commonly include bouts of sneezing, watery eyes, and a clear or slightly cloudy nasal discharge. Affected cats may also display mild lethargy and a reduced interest in food, often due to a temporary loss of their sense of smell.
Owners should seek veterinary advice if symptoms progress or persist. Immediate professional attention is warranted if the cat shows signs of difficulty breathing, such as open-mouth breathing or excessive panting.
The cat’s appetite is a serious indicator; a cat that refuses to eat for more than 24 hours should be seen by a veterinarian due to the risk of hepatic lipidosis. Changes in discharge color or consistency, such as becoming thick, yellow, or green, suggest a secondary bacterial infection requiring antibiotics.
Any sign of fever, severe eye inflammation, or painful ulcers in the mouth should also prompt a consultation. Supportive care at home involves gently cleaning the face to remove discharge and ensuring the cat remains hydrated.