Influenza (flu) is an infection caused by influenza viruses. It affects your upper respiratory tract (your nose, throat and mouth) and can range from mild to severe.
It can cause a range of symptoms, and usually lasts from a few days to a couple of weeks. Influenza can be very mild or considerably more serious, and often comes on very suddenly and without warning.
Most people who get flu will be fine within a few days to two weeks, but some people, particularly those classed as vulnerable such as the elderly, can get complications which can lead to conditions such as pneumonia. This may be life-threatening.
Who gets the flu?
Anyone can get the flu, but some groups are more vulnerable to it. This includes babies, pregnant women, people over the age of 65 and the elderly, and people with certain health conditions that limit their immune systems, such as diabetes and heart disease. Asthma sufferers are more prone to it too.
The flu is highly contagious, and spreads when you come into contact with another person who has it, or if you come into contact with the things that somebody coughs or sneezes on. It’s very easy to catch it as you go about your day-to-day life, so it’s important to take preventative measures to limit your chances of catching flu. These measures include washing your hands when you go to the toilet and sanitising your hands when you eat.
How common is flu?
The flu is very common. About 9% of the world population gets the flu each year. Up to one billion are infected, and there are approximately three to five million cases which are severe. Between three and five hundred thousand cases result in death .
When we present you with stats, data, opinion or a consensus, we’ll tell you where this came from. And we’ll only present data as clinically reliable if it’s come from a reputable source, such as a state or government-funded health body, a peer-reviewed medical journal, or a recognised analytics or data body. Read more in our editorial policy.
What causes flu?
Flu is caused by catching the influenza virus. It’s highly contagious and it’s usually transmitted through infected people coughing or sneezing. This spreads the virus into the air, where people can breathe it in and become infected. The virus can also live on surfaces, and be transmitted when you touch them.
What are the symptoms of flu?
Common symptoms of flu can include but are not limited to:
feeling nauseous and being sick
stomach pain and diarrhoea
appetite loss or changes in eating habits
a sore throat and dry cough
feeling tired and achy
a high temperature of 38°c or above which comes on quickly
Can flu lead to other problems?
The flu is usually not dangerous, and most people will recover from it without needing an intervention or medication. But if you’re in a more vulnerable health group it can create complications due to your immune system not being strong enough to defeat the virus on its own. A secondary infection may progress, such as pneumonia, or it may worsen pre-existing illnesses, such as asthma, diabetes or heart disease.
Some of the effects of flu in those of us with chronic medical conditions can be much more serious, such as a persistent pressure in the chest, difficulty breathing, seizures or dizziness and confusion.
What medications are there for the flu?
There are a range of medications that can help ease flu symptoms. There are treatments such as Tamiflu, which is both a treatment and a prevention method. Tamaflu, otherwise known as Oseltamivir, has been proven to reduce the length of flu illness in both adults and children by around one to two days, and reduces the duration of symptoms of flu even if it’s taken more than two days after the symptoms started. If you are particularly vulnerable to flu, it’s recommended that you get the flu vaccine regularly.
Is there a ‘best’ treatment for flu?
The flu vaccine is recommended every year for certain groups, such as the elderly, pregnant women, babies, and people with health conditions. Getting the flu vaccine is the most effective way of protecting yourself, and potentially those around you since flu is contagious. The exact treatment of infections will depend on you and your symptoms, and options can be discussed with a doctor or clinician.
Does flu always need treatment?
In some cases, flu can be managed without the need for treatment by resting and sleeping. Taking over-the-counter medications such as paracetamol and ibuprofen to lower your body temperature and alleviate aches and pains, and staying hydrated, can also help.
Have something specific you want to know? Search our info below, or ask our experts a question if you can’t find what you’re looking for.
How is the flu diagnosed?
Flu, and other kinds of viruses, can only be confirmed by a doctor after a nose or throat swab has returned positive results. Treatment is similar for any "flu like" illness, so it’s best to talk to a clinician about your symptoms. The right course of action for you can then be decided based on your individual needs.
Are there different types of flu?
There are four types of influenza viruses: A, B, C and D. Influenza A and Influenza B cause most of the flu strains that trouble humans like the annual and seasonal flu that a lot of us experience. Influenza C usually only causes minor symptoms in people and its effects are much less severe. Influenza D, on the other hand, does not cause illness in humans.
Are there tests for flu?
There are a range of tests for flu, including both rapid tests and laboratory tests. Tests are not always needed when it comes to a diagnosis. A clinician can usually decide if you have the flu having spoken with you about your symptoms.
Can you get side effects from flu treatment?
Side effects of flu treatment are rare, but you can get them. Side effects include nausea and vomiting and if you experience a severe allergic reaction, rashes, itching, swelling and dizziness. You’re very unlikely to have an allergic reaction, but if you experience these symptoms, you should seek emergency medical attention immediately.
Does flu treatment always work?
The flu vaccine is very effective. Not only does it reduce the severity of symptoms, but it also prevents millions of people from getting the flu each year. A 2021 study demonstrated that in adults, the flu vaccination was shown to result in a 26% lowering in the risk of ICU admissions, as well as a 31% lowering in the risk of flu related deaths compared to those who were unvaccinated. Tamiflu has also been shown to be effective for both prevention and treatment of flu. It has been shown to protect against flu in 58-89% of healthy adults, and 92% of the elderly population. Tamiflu reduces the severity of symptoms, and lessens lower respiratory tract complications and the need for hospitalisation which often occurs in severe cases of flu.
Why should I buy flu treatment online with Treated?
Your health, wellbeing, and happiness is at the forefront of everything we do here at Treated; that means empowering you to choose your medication from our treatment options.
We’ll stay in touch with you to make sure that your treatment is working the way it should. And if you’ve got any questions about your medication, our clinicians are on hand to help you. You just need to sign in to your account and send them a message.
Mørland, B., Brantsæter, A.B., Fuglesang, J.E., Haaheim, L.R., Løvoll, Ø., Salmén, R., Sjursen, H., Kristiansen, I.S., Wisløff, T., Ørjasæter Elvsaas, I.-K. and Nilsen, E. (2005).
Effect of Oseltamivir (Tamiflu®) for the Prevention and Treatment of Influenza During an Influenza Pandemic. PubMed. Oslo, Norway: Knowledge Centre for the Health Services at The Norwegian Institute of Public Health (NIPH).
Disclaimer: The information provided on this page is not a substitute for professional medical advice, diagnosis, or treatment. If you have any questions or concerns about your health, please talk to a doctor.
This treatment category isn't suitable for the gender you have selected.
If you made a mistake on the gender selection, you can amend this by pressing 'Cancel' below and changing your gender. If you entered the correct gender but made a mistake on the treatment category selection, you can choose a different category by pressing 'Choose other treatment' below.