Almost everyone has had this one illness. Generally this disease occurs due to the infection of the virus that attacks the respiratory tract. This one disease has a relatively short incubation period. Various symptoms of this disease generally only occurs within a few days after the patient is infected. The flu is a contagious disease. Thus, this disease will be able to move from one person to another. The mechanism of transmission can occur so easily. When the sufferer is in one room along with a healthy person, then he sneezes or coughs, then the discharge is exposed to another healthy person and then at the same time the healthy person is interacting with the nose or mouth, the transmission of the virus the cause of flu will occur easily. The period of transmission of this flu can occur one day before symptoms muncil and about 6 days later.