Feline infectious peritonitis (FIP) is a fatal, incurable disease that affects cats.It is caused by Feline Infectious Peritonitis Virus (FIPV), which is a mutation of Feline Enteric Coronavirus (FECV) - (Feline coronavirus FCoV).Experts do not agree on the specifics of genetic changes that produce the FIPV.t is caused by Feline Infectious Peritonitis Virus (FIPV), which is a mutation of Feline Enteric Coronavirus (FECV) - (Feline coronavirus FCoV).
Some people get mild cases of only a few days, o â¦ thers get severe cases of a few weeks or more and are hospitalized. On average, the symptoms of the flu generally last 3 - 10 days but the H1N1/09 virus lasts more typically 4 - 7, although a cough and fatigue may persist for up to 2 weeks.
Flu symptoms can last a week or more. A child can pass along a flu virus for seven or more days after the virus has entered his body. Symptoms begin one to four days after the virus has infected the body, but it is possible to pass along the virus before symptoms appear.