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How long is the flu contagious for?

Medically reviewed by Carmen Pope, BPharm. Last updated on Aug 31, 2023.

Official answer


The flu is contagious from the day before you start showing symptoms till approximately five to seven days after your symptoms start. Generally, most people are contagious for about a week in total, although some experts believe the most contagious period is the first three to four days of harboring the virus. If you still have a fever, that is a sign that you will still be contagious. Children may be contagious for longer until all their symptoms have resolved.

Contagious means that the flu can spread from one person to another. There are several different ways you can spread the flu, such as:

  • Sneezing or coughing into the air. When you do this, droplets of moisture from your lungs and mouth that contain the flu virus escape into the air. Uninfected people breathe these in, or they land on their eyes or mouth or they touch hard surfaces contaminated by the virus. If their immune system is not able to fight the virus, then they will develop the flu.
  • Not washing your hands properly. If you are constantly blowing your nose or coughing, your hands easily become contaminated with the flu virus. Then when you touch hard surfaces, such as taps, bench tops, or doorknobs, you leave droplets of the virus behind. The virus can live on hard surfaces for up to 48 hours. Wash your hands regularly when you are sick and always after blowing your nose or coughing into your hands.

Always cover your nose and mouth with a tissue when you sneeze or cough, use tissues only once, and then discard them hygienically in a rubbish bin. Wash your hands afterward.

You should stay off work or school for at least 24 hours after your fever has gone down by itself, or for longer if you are still sneezing and coughing a lot.

Even though over the counter cough and cold medicines may help you feel better, they will not stop the spread of the virus and you risk infecting all your colleagues and school friends if you return to work or school too early. Antiviral medicines, such as baloxavir marboxil (Xofluza), oseltamivir (Tamiflu), peramivir (Rapivab), and zanamivir (Relenza), can shorten the time you are sick with the flu virus by one to two days and may also shorten the length of time you are contagious for.

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