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Flu Information

Frequently Asked Questions (FAQs) about the Flu

1. What is the flu?

The flu (short for "influenza") is an illness caused by viruses. Flu virus can live in a person's nose, throat, and lungs. There are many types of flu viruses. The most common each year is the "seasonal flu." Another flu virus you will hear about this year is H1N1, also known as Swine Flu.

2. When is flu season?

Flu season in Massachusetts usually begins in December and lasts through March.

3. Is the flu dangerous?

The flu can be a serious illness. Every year, about 200,000 people in the US are hospitalized with the flu and 36,000 die from flu-related complications. Anyone can get the flu, and most people recover within 1 to 2 weeks. But some people can become very sick. People who are at highest risk for becoming very sick from the flu include:

  • Adults age 50 or older
  • Children under 5 years old
  • Pregnant women
  • People with chronic illnesses
  • People with weak immune systems

4. How is the flu spread?

Flu viruses live in your nose and throat. When an infected person coughs, sneezes, or talks, flu viruses are spread into the air. People nearby can breathe in the viruses and become sick. An infected person can spread the flu a day before symptoms appear and can remain contagious for up to a week later. A child with flu can be contagious longer than a week.

Flu viruses, including the H1N1 virus, can also live on surfaces like doorknobs, phones, and toys for several hours. It can be very difficult to keep these types of surfaces free of virus, which is why washing your hands often is so important.

5. What are flu symptoms?

Flu symptoms appear 1 to 5 days after exposure, and may include:

  • Fever (102°-104°), lasting 3-5 days
  • Chills
  • Headaches
  • Sore throat
  • Severe muscle aches
  • Tiredness, which can be extreme and can last two weeks or more
  • Dry cough
  • Runny or stuffy nose

Serious complications from flu include dehydration, pneumonia, bronchitis, and sinus/ear infections. The flu can also make chronic health problems worse.

6. What if I think my child has the flu?

Both seasonal flu and H1N1 flu can be dangerous for children. Seek emergency medical care if your child becomes ill and experiences any of the following warning signs:

  • Fast or trouble breathing
  • Bluish or gray skin color
  • Not drinking enough fluids
  • Not urinating as much as usual
  • Severe or persistent vomiting
  • Not waking up or interacting as usual
  • Extreme irritability
  • Fever returns after being gone for a day, or significant change in the fever pattern

Again, seek emergency medical care if your child becomes very ill and experiences any of those warning signs.

7. What if I need to see a doctor while I have the flu?

If you have active flu symptoms when you come into our hospitals or health centers (sneezing, coughing, or fever), please tell us right away. We can give you a mask to wear while you are here.

8. Who should get vaccinated?

Anyone who wants to reduce their risk of getting the flu should get vaccinated. However, during flu seasons when vaccine supplies are limited or delayed, priority should be given to people at high risk for becoming very sick from the flu and their caregivers.

9. If you get a flu shot can you still get the flu?

The flu shot is 70-90% effective in preventing flu or at least reducing symptoms. It usually takes two weeks after the shot to develop maximum protection, which then gradually wears off. The flu shot does not cause the flu.

10. How can I prevent the flu?

These simple actions can protect you from getting the flu and help stop the spread of germs:

  • Get a flu shot every year
  • Get a pneumonia shot if you are age 65 or older, or if you have a medical condition (like diabetes, asthma, or heart disease)
  • Wash your hands often
  • Avoid touching your eyes, nose, or mouth
  • Wipe down door handles, water faucets, phones, and other household items that are frequently touched by family members
  • Avoid close contact with sick people
  • Stay home when you are sick to prevent others from catching your illness
  • Cough or sneeze into the inside of your arm, not your hands.
  • Dispose of tissues properly, and wash your hands after using tissues.

Other good habits, such as getting plenty of sleep, engaging in physical activity, managing stress, drinking water, and eating good food, will help you stay healthy during the winter and all year.

11. How can I get current information about the flu?

For more information about the flu you can visit the flu pages on the Massachusetts Department of Public Health web site.


Sources: Cambridge Public Health Department (Public Health Nursing Program), Massachusetts Department of Public Health, and Boston Public Health Commission.




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