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.
Most otherwise healthy individuals actually have the flu virus infection for approximately one to two weeks but the main symptoms described above last from 3-10 days and most of the symptoms will begin to subside in about one week.o answer to âhow long does the flu last?â I offer this information. First, there is a period of incubation from the time you are exposed to the flu virus to the time you start suffering the signs and symptoms and that period is approximately 1-5 days.