Flu (influenza): Symptoms and treatment
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COVID-19 and the flu can have similar symptoms. If you start to develop any of the symptoms below, follow the same precautions taken for COVID-19.
Flu symptoms may vary from person to person. Some people only get mildly ill. Others get very sick.
Flu symptoms appear 1 to 4 days after exposure to the virus. Usually they include the sudden appearance of:
- muscle aches and pain
Other common symptoms may include:
- fatigue (tiredness)
- loss of appetite
- sore throat
- runny or stuffy nose
Some people (especially children) may also have:
- nausea and vomiting
Additional symptoms to watch for in children
As a parent, you know your child best. Talk to a health care provider right away if you notice any of these symptoms:
- not drinking or eating as usual
- not waking up or interacting with others
- irritable (not wanting to play or be held)
People infected with the flu virus can spread it to others:
- starting 1 day before the first symptoms
- until approximately 5 days after the first symptoms
Similarities between the symptoms of the flu and COVID-19
The flu and COVID-19 are different viruses. They're very contagious and have similar symptoms. This can make it hard to tell the difference between the flu and COVID-19 when symptoms appear.
If you start to develop symptoms, follow the same precautions taken for COVID-19.
This year is more important than ever for everyone 6 months and older to get the flu shot. This will help prevent the flu and flu-related complications. Preventing the flu will also help reduce stress on the health care system during the COVID-19 pandemic.
If you get the flu
If you do get sick, stay home to help prevent the spread of the flu or potentially COVID-19. Avoid close contact with other people until you feel well enough to get back to your usual day-to-day activities. This is especially important for people who have higher chances of developing complications from the flu.
It can be hard to tell the difference between symptoms of the flu and COVID-19. You can only confirm if you have the flu or COVID-19 with a test. If you have symptoms of the flu and haven’t received a negative COVID-19 test, follow COVID-19 prevention measures to help keep others safe.
Most people recover from the flu in 7 to 10 days.
If you're a person at high risk of flu or COVID-related complications and develop symptoms, contact a health care provider. Tell them about your symptoms over the phone before your appointment and follow their instructions. That way, they can arrange to see you without exposing other people.
If you need immediate medical attention, call 911 and tell them your symptoms.
Possible complications of the flu
- pneumonia and respiratory failure
- worsening of chronic health conditions
Other severe outcomes of the flu
How the flu is diagnosed
The flu is usually diagnosed by your health care provider based on:
- laboratory tests (nose or throat swab)
Flu symptoms can be treated with:
- fluids, like water
- medication to reduce any fever or aches
In some cases a health care provider may prescribe medication, especially if you're:
- at high risk for flu-related complications
- very sick with severe symptoms
Over-the-counter cough and flu medicine should not be given to children younger than 6 years old. It's only safe to do so if you're advised to by your health care provider.
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