Some of the first warning signs of the flu include:
- Muscle aches
- Malaise (feeling of being unwell)
- Sinus and ear infections
- Vomiting (more common in children)
- Diarrhea (more common in children)
The flu is common, affecting 5%-15% of the population every year. In most cases, the flu goes away on its own in a few days.
Early detection of flu symptoms can help you seek timely treatment and minimize the duration of an infection.
What causes the flu?
The flu is caused by a family of influenza viruses, categorized as A, B, C, or D. The influenza virus can be transmitted in the following ways:
How long are you contagious after the flu?
Some people who are infected with the flu virus can spread the infection before they even realize they are sick, starting from the day before flu symptoms appear and up to 7 days after they have been ill.
Others, particularly infants and those with compromised immune systems, may be able to infect others for even longer periods. Even though the average incubation period for influenza is 1-4 days, certain individuals might be infectious for up to 2 weeks.
What are complications of the flu?
Rare but severe complications of the flu include:
- Heart inflammation (myocarditis)
- Brain inflammation (encephalitis)
- Muscle tissue inflammation (myositis, rhabdomyolysis)
- Multi-organ failure (respiratory or kidney failure)
What are home remedies for the flu?
Once flu symptoms develop, there is nothing you can do but let the infection run its course. Home remedies that may help speed up recovery include the following:
- Drinking plenty of water
- Taking vitamin C
- Using aromatherapy oils, such as peppermint and eucalyptus, to relieve congestion
- Sitting in a steam bath to clear the sinuses
- Gargling salt water to soothe a sore throat
Should I get the flu vaccine?
Flu vaccines protect against the influenza viruses that are expected to be the most common during the flu season. Most flu vaccines are administered through an injection, although a nasal spray flu vaccine is also available.
The Centers for Disease Control and Prevention (CDC) advises that all children ages 6 months and older in the United States should get the flu vaccine once a year, ideally before the end of October.
Because the influenza virus evolves rapidly, new vaccines are developed to ensure better protection against the virus. With the ongoing COVID-19 pandemic, it is possible to get infected with both the flu and COVID-19 at the same time. Therefore, getting vaccinated for the flu in addition to COVID-19 is crucial to avoid serious illness.
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Arbeitskreis Blut, Untergruppe «Bewertung Blutassoziierter Krankheitserreger». Influenza Virus. Transfus Med Hemother. 2009;36(1):32-39. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2928832/
National Foundation for Infectious Diseases. Flu (Influenza). https://www.nfid.org/infectious-diseases/influenza-flu/
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