How long does the flu virus usually last for?

A number of different viruses cause flu-like symptoms, so the length of time you have the flu for varies from person-to-person, depending on the cause. How bad your symptoms are, and how long you have them for, also depends on what other medical conditions you currently have or if you are pregnant, and how compromised your immune system is at the time of catching the flu.

There are four main types of influenza viruses - A, B , C, and D. A and B are responsible for most cases of human flu during winter, type C generally causes a mild illness that is not very contagious, and type D viruses primarily affect cattle.

Type A and B flu viruses are the most common type to cause pandemics or epidemics. But even if two people have caught, for example, a type A influenza virus, symptoms may be mild in one person and severe enough to require hospitalization in another. Flu-associated deaths range each year from a low of about 3,000 to a high of about 49,000 people. Flu symptoms usually occur between one to four days after exposure to the virus and most people recover within a week, although you may feel tired or have a cough for much longer.

You should contact a doctor if you have another medical condition such as asthma, heart problems or diabetes and are finding it difficult to maintain good symptom control, or if your symptoms are severe. Be careful not to pass the flu on to those around you - the virus can be easily spread through sneezing or coughing or you may leave the virus on surfaces that you touch. Experts consider somebody with the flu infectious one day before symptoms begin and up to five to seven days after becoming sick. Some people may remain infectious for an even longer time. The best way to prevent the flu is to get a flu shot every year.