16 Questions About Flu

What is influenza?

Flu is an infection that causes symptoms such as fever, cough, and body aches; the most common type is "seasonal" flu, which comes in different forms such as "type A" and "type B." Flu is caused by a virus, the medical term for which is "influenza."

What other types of influenza are there?

In addition to seasonal flu, there is also "swine flu," which caused a worldwide outbreak (a "pandemic") in 2009 and 2010, and avian flu, a severe form of flu whose pathogen first infects poultry.

What are the most common symptoms of flu?

Flu can cause:

Fever (temperature > 37.8°C)

Extreme fatigue

Headache or body aches

Cough

Sore throat

Runny nose

Symptoms may occur suddenly.

Is the flu dangerous?

Possibly. Most people with the flu recover on their own without any sequelae, but some will need to see a doctor. Because the flu can cause pneumonia (a serious lung infection) and can be fatal, it is important to take precautions first.

The following groups of people are more likely to develop severe illness from influenza:

≥ 65 years

●Young children (5 years old, especially 2 years old)

Pregnant women

●People with certain diseases

Family members of people with the flu sometimes also need medication to prevent the disease.

Is there a test for the flu?

Yes. In most cases, your doctor can tell whether you have the flu based on your symptoms. However, sometimes additional tests may be needed, such as when the flu is likely to be causing another problem.

What should I do if I have the flu?

You should rest at home, drink plenty of water, and you can also use acetaminophen to reduce fever and relieve pain.

˂Aspirin and medicines containing aspirin are prohibited for children under 18 years old, otherwise it may cause severe Reye's syndrome.

Most people with the flu get better on their own within 1 to 2 weeks, but you should contact your doctor if you:

Difficulty breathing or shortness of breath

Pain or pressure in the chest or abdomen

Sudden dizziness

Confusion

Severe vomiting

Children with influenza should see a doctor if they:

Rapid breathing or difficulty breathing

● Skin color turns blue or purple

Not drinking enough water

●Unable to wake up or lack of interaction

●Irritable, unwilling to be hugged

Fever or cough reappears after flu subsides

Fever with rash

When patients with influenza visit a doctor, they should inform the medical staff as soon as possible, and the latter will provide masks or isolate the waiting area to prevent the spread of infection.

Regardless of whether or not you seek medical attention, people with influenza should stay home until they recover and return to work or school only after they have been fever-free for at least 24 hours without the use of medications such as acetaminophen. If you come into contact with patients at work (such as in a hospital or clinic), you may need to wait until your cough subsides before returning to work. In addition, be sure to cover your mouth and nose with your elbow when you cough or sneeze.

Can the flu be treated?

Yes. Antiviral medicines can help prevent some problems with the flu, and some people may need them, at the discretion of their healthcare provider. Antibiotics are not effective for the flu.

How to prevent influenza?

The following measures can be taken:

●Wash your hands frequently with soap.

●Stay away from patients

● Get a flu shot every year – The flu vaccine has different effectiveness in different years, but even in years with lower effectiveness it can still provide some protection and prevent serious illness from the flu.

What is the flu vaccine?

Vaccines can prevent some serious or fatal infections, and the flu vaccine can prevent the flu. Using a vaccine is also called "vaccination" or "immunization." Existing flu vaccines do not protect against bird flu.

Are there different forms of flu vaccines?

Yes, including:

●Intramuscular injection, usually in the upper arm

Nasal spray

Your doctor can help you decide which vaccine is best for you.

Who should be vaccinated and when?

All people aged 6 months or older should receive an influenza vaccine every year. This vaccine is especially important for certain high-risk groups.

The best time of year to get a flu shot is before winter begins, and it should be given as soon as it is available in your area. Children aged 6 months to 8 years may need 2 doses of the vaccine for best results, depending on how many previous doses of the flu vaccine have been given.

Why should I get a flu shot?

It can prevent you and those around you from getting sick. It can also prevent you from getting seriously ill or dying if you get the flu even though you’ve been vaccinated. The flu vaccine is more effective in some years because vaccine developers can’t accurately predict how the flu virus changes from year to year, and it takes months to develop a new vaccine.

Some people think the flu vaccine doesn't work because they've heard about people who got the flu shot and still got the flu, but this doesn't mean the vaccine doesn't work. Many people who get sick after getting the flu shot don't actually have the flu, but other viruses, so the flu vaccine doesn't help.

Even in years when the vaccine is less effective, it can still help prevent some cases of the flu and can help prevent severe illness and flu outbreaks.

What are the side effects of the flu vaccine?

There are usually no side effects, but when they do occur, they can cause:

●Injections may cause redness, mild swelling, or pain at the injection site

Mild fever

Mild rash

Headache or body aches

Vaccines can sometimes cause more serious side effects, such as severe allergic reactions, but these are extremely rare.

Does the flu vaccine cause the flu?

No. People sometimes get sick after getting a flu shot, but this is often because they had the flu or another viral infection before getting the shot.

What should I do if I have an egg allergy?

People are sometimes concerned about this because some forms of the flu vaccine contain small amounts of eggs, but the amounts are very small and not enough to cause an allergic reaction. If you have an egg allergy, you should still get the flu vaccine.

What else can I do to prevent the flu?

In addition to getting a flu shot every year, you can also:

● Wash your hands frequently with soap or use alcohol-based hand sanitizer

●Stay away from sick people

Antiviral medicines can help prevent the flu if you are exposed, but they are not suitable for everyone. Also, antiviral medicines are only effective if they are started soon after exposure or as soon as symptoms appear.

You should also take the following steps to protect others:

● If you have the flu, stay home from work or school until you have been fever-free for at least 24 hours without the use of fever-reducing medicines such as acetaminophen. If you work in a hospital or clinic, you may need to stay home longer if you still have a cough.

●When coughing or sneezing, you should cover your mouth and nose with the inside of your elbow.

References:

1. Influenza. Written by the doctors and editors at UpToDate, 2021.

2. Ge Mingchan. Influenza transmission routes and prevention measures[J]. Longevity, 2020, 396(01):15-17.