How Long Does The Flu Last?

The flu can come on unexpectedly – the flu has a short incubation period, between 1 to 4 days, so you can start showing symptoms very quickly after being exposed to the virus. Symptoms of the flu can appear quite suddenly and intensely, so it is common to be fine one day and then be out of action the next day with the flu.

The most severe symptoms generally last 2 to 3 days – the start of the flu is when the infection is at its worst, so the symptoms are at their most severe. During this time you will most likely be confined to bed with fatigue, weakness, and a high fever.

You usually have symptoms for around 3 to 7 days – once you’re through the worst of the flu, you will still have some lingering symptoms to recover from, which can include a dry cough, fatigue, and weakness. It’s recommended that even if you are feeling a little bit better, you should still rest as much as possible to help your body recover.

You should make a full recovery within 2 weeks – while your body may have fought off the infection successfully, you may not feel 100% for up to 2 weeks after being infected. Most of your symptoms should have subsided by this point, but it’s normal to feel weak and tired while your body recovers from the infection.

Go see a doctor if your symptoms last longer – if you still feel very ill after a week then it may mean that you have an underlying condition that is stopping you from recovering, or the flu is causing more serious health complications. If you’re getting worse or not feeling any better after a week, call NHS 111 or go and see your doctor.

For more information on the flu, you can read our page on flu symptoms here.

How do I know if I have the flu?

A lot of illnesses have “flu-like” symptoms – it can be hard to tell whether or not you have the flu because it shares a number of symptoms with other infections and conditions, especially the common cold.

Flu and colds – the flu and the common cold can be mistaken for one another because they share a lot of the same symptoms, such as fever, a cough, and a sore throat. The rule of thumb to tell the difference between the two is that the symptoms of the flu may come on quickly and more severely than a cold, which is usually milder. You can find out more on the difference between a cold and the flu here.

Flu and meningitis – meningitis is an inflammation of the tissue that surrounds and protects the brain and spine, and can cause serious health complications if left untreated. The key symptoms to look out for include a severe headache, stiff neck, and a dislike of bright lights, which mean that someone may have meningitis. For more information, read our page on the symptoms of meningitis.

How long am I contagious with the flu?

You may be contagious before you know you have flu – the influenza virus spreads very easily, even if you don’t currently have any symptoms. After being infected, you are contagious for a day even before you develop any symptoms of the flu.

While you have symptoms, you are highly contagious – it may go without saying, but when you at struggling with a full-blown flu infection you are at your most contagious. When you have the flu, you should limit your interactions with other people as much as possible to avoid spreading it to others.

You will still be contagious while you’re recovering – even if you’re feeling a bit better after your bout with the flu, and feel like you’re on the road to recover, you’re still able to pass on your infection to other people. You are still contagious for up to a week after becoming sick.

If you’re contagious, stay at home – nobody likes getting the flu, so try to stay away from other people if you’re still contagious. Flu spreads especially quickly in enclosed spaces, such as at work or school, so going back before you’ve fully recovered puts other people at risk of catching the flu from you.

How do I get rid of the flu?

There is no “cure” for the flu – while there’s no treatment that will get rid of the flu, there are a number of things you can do that can help to ease your symptoms and speed up your recovery.

Stay hydrated – the flu causes dehydration by increasing your body temperature (fever), which means that you sweat more and breathe faster to try and regulate your body temperature. In more severe cases, you can also lose fluids as a result of diarrhoea and vomiting. Making sure that you drink enough fluids, preferably water, will help you fight off the infection faster.

Get plenty of rest – sleep is necessary for the body to repair itself, especially when you are feeling sick. Making sure that you rest gives your body the opportunity to fight off the infection and recover faster, while being too active when you have the flu means your body may have less energy to spend on getting better.

Over-the-counter medication can help to alleviate symptoms – painkillers and anti-inflammatory medications, such as paracetamol and ibuprofen, can help to reduce muscle aches and fever caused by the flu. Speak with a pharmacist before giving any medication to children, as some over-the-counter medications are not suitable for young people.