Understanding Feline Coronavirus Infection: Causes & Pr

The Pathogen: The feline coronavirus, belonging to the Coronaviridae family and genus Coronavirus, is the causative agent. This virus is sensitive to liposoluble agents like ether and has a low resistance to external environments. It loses its activity within one day at room temperature, and is typically killed by common disinfectants. However, it is more resistant to phenol, low temperatures, and acidic conditions.

Cats of all ages are susceptible to infection and illness, with those between 1 to 2 years old and the elderly being particularly vulnerable. Young cats are also prone to illness during pregnancy, weaning, immune deficiency, and under stress. Purebred cats have a higher incidence rate than domestic cats.

The disease can be transmitted through the digestive tract or by vectors such as insects. The feces and urine of infected cats can release the virus, making them a significant source of transmission. Female cats can vertically transmit the virus to their kittens.

Primary Symptoms:

The incubation period is long, with natural infections typically taking 4 months or longer, with most cases being asymptomatic.

There are two common clinical types:

1. Exudative (Wet) Type: The initial symptoms are often subtle or nonspecific. Cats may gradually lose weight, experience a decrease in appetite, or intermittent anorexia, and become weak. Their body temperature may rise to 39.7 to 41.1 degrees Celsius, with an increase in white blood cell count. Some may exhibit mild upper respiratory symptoms. After 42 days, 75% of the affected cats develop ascites, 25% have pleural effusion, and there is an increase in pericardial fluid. At this stage, the cats may experience difficulty breathing, anemia, and weakness. The course of the disease lasts from 2 to 4 weeks, with most cases ending in death.

2. Nonexudative (Dry) Type: This type primarily presents with granulomas in various organs, accompanied by corresponding clinical symptoms. Abdominal organs such as the liver and mesenteric lymph nodes are most severely affected. Eye infections may lead to corneal edema, inflammation of the iris and lens, cloudy aqueous humor, and redness with clots. When the central nervous system is damaged, cats may exhibit ataxia, mild paralysis, seizures, hypersensitivity, and peripheral neuritis. The course of the disease lasts from 1 to 8 weeks, with most cases ending in death.

Currently, vaccines are available for immunization. Prevention also involves maintaining the cleanliness of the cat's living environment, eliminating bloodsucking insects and rodents from the cattery, and thoroughly disinfecting contaminated areas with 0.2% formaldehyde or 0.5g/L chlorhexidine.

As of now, there is no effective specific treatment drug. The prognosis for cats with clinical symptoms is generally poor. Supportive therapy, including the use of immunosuppressants (such as corticosteroids), and the combination of ampicillin or tetracycline with vitamins, can extend the life of affected cats to some extent, but cannot cure the disease.