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Flu Background Information

Flu Background Information (OHA)

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Flue Background

What we know about seasonal influenza

In Oregon, seasonal influenza often peaks in January to March. Every flu season is different, and influenza can affect people differently. Even healthy children and adults can get very sick from the flu and spread it to others. Over a period of 30 years, between 1976 and 2006, CDC estimates of flu-associated deaths in the United States range from a low of about 3,000 to a high of about 49,000 people.

Transmission

Influenza is a virus that spreads from person-to-person, through the air and on hard surfaces as well as in droplets from sneezes and coughs.

Risks

Most people will recover from the flu in less than two weeks. For some people, the flu can be a
very serious, even deadly disease. Anyone could have complications from the flu, but those at
highest risk are:

  • People 65 and older
  • Pregnant women
  • Those with chronic medical conditions like asthma, diabetes, heart disease
  • Young children
  • Those with weak immune systems due to disease or medication, HIV, cancer or those on chronic steroids

Common complications for high-risk groups include:

  • Pneumonia
  • Bronchitis
  • Sinus and ear infections

Worsening chronic conditions (e.g., asthma, chronic heart disease)

Signs and symptoms of flu

Illness from the flu can last for 10 days or more. People who have the flu often feel some or all of these signs and symptoms:

  • Fever* or feeling feverish/chills
  • Cough
  • Sore throat
  • Runny or stuffy nose
  • Muscle or body aches
  • Headaches
  • Fatigue (very tired)
  • Some people may have vomiting and diarrhea, though this is more common in children than adults.

*It is important to note that not every one with flu will have a fever.

Prevention

  1. Flu vaccine for every one over 6 months!
  2. Wash your hands often. Use alcohol based hand rubs when soap isn’t available.
  3. Limit close contact with sick people.
  4. Limit your contact with others when sick.
  5. Cover your nose and mouth when you cough or sneeze.
  6. Avoid touching your eyes, nose and mouth.
  7. Clean and disinfect surfaces that may have germs.

Care and Treatment

In most cases people with flu have mild illness and need increased rest, fluids, and acetaminophen or ibuprofen for fever. Generally, people with signs of flu should stay home and avoid contact with others. Some people do need emergency care. Antiviral drugs are recommended for anyone in one of the high-risk groups mentioned above or who is sick enough to need hospital care. A health care provider will decide if antiviral drugs are necessary. People should get medical help right away if
they have any of the following emergency signs:

In children
  • Fast breathing or trouble breathing
  • Bluish skin color
  • Not drinking enough fluids
  • Not waking up or not interacting
  • Being so irritable that the child does not want to be held
  • Flu-like symptoms improve but then return with fever and worse cough
  • Fever with a rash
In adults
  • Difficulty breathing or shortness of breath
  • Pain or pressure in the chest or abdomen
  • Sudden dizziness
  • Confusion
  • Severe or persistent vomiting
  • Flu-like symptoms that improve but then return with fever and worse cough

In addition to the signs above, get medical help right away for any infant who has any of these signs:

  • Are unable to eat
  • Has trouble breathing
  • Has no tears when crying
  • Significantly fewer wet diapers than normal

What we know about inactivated influenza vaccine

Flu vaccine can:

  • Keep you from getting flu.

  • Make flu less severe if you do get it.
  • Keep you from spreading flu to your family and other people.
  • Take about 2 weeks to develop protection after vaccination and protection lasts through the flu season.

Flu vaccine cannot prevent:

  • Flu that is caused by a virus not covered by the vaccine.
  • Illnesses that look like flu but are not.

Recommendations:

  • A dose of flu vaccine is recommended every flu season.
  • Some children 6 months through 8 years of age may need two doses during the same flu season.
  • Everyone else needs only one dose each flu season.

Some people should not get this vaccine. So that the person giving you your vaccine can offer advice for your condition, tell the person who is giving you the vaccine:

  • If you have any severe, life-threatening allergies. If you ever had a life-threatening allergic reaction after a dose of flu vaccine or have a severe allergy to any part of this vaccine, you may be advised not to get vaccinated. Most, but not all, types of flu vaccine contain a small amount of egg protein. People with egg allergies can and should still get the flu vaccine. Those with severe egg allergies should be advised to receive their vaccine in a medical setting able to recognize and manage severe allergic reactions.
  • If you ever had Guillain-Barré Syndrome (also called GBS). Some people with a history of GBS should not get this vaccine. This should be discussed with your doctor.
  • If you are not feeling well. It is usually okay to get flu vaccine when you have a mild illness, but you might be asked to come back when you feel better.

Contents:

  • There is no live flu virus in flu shots. They cannot cause the flu.
  • There are many flu viruses, and they are always changing. Each year a new flu vaccine is made to protect against three or four viruses that are likely to cause disease in the upcoming flu season. Even when the vaccine doesn’t exactly match these viruses, it may still provide some protection.
  • Some flu vaccine vials have multiple doses of flu vaccine and contain a very small amount of a mercury-based preservative called thimerosal. Studies have not shown thimerosal in vaccines to be harmful, but flu vaccines that do not contain thimerosal are available.

Risks of a vaccine reaction

With any medicine, including vaccines, there is a chance of reactions. These are usually mild and go away on their own, but serious reactions are also possible. Most people who get a flu shot do not have any problems with it. If problems occur, they usually begin soon after the shot and last one or two days.

Minor problems following a flu shot include:

  • Soreness, redness or swelling where the shot was given
  • Hoarseness
  • Sore, red or itchy eyes
  • Cough
  • Fever
  • Aches
  • Headache
  • Itching
  • Fatigue

More serious problems following a flu shot can include:

  • There may be a small increased risk of Guillain-Barré Syndrome (GBS) after inactivated flu vaccine. This risk has been estimated at one or two additional cases per million people vaccinated. This risk is much lower than the risk of severe complications from flu, which flu vaccines can prevent.
  • Young children who get the flu shot along with pneumococcal vaccine (PCV13) or DTaP vaccine at the same time might be slightly more likely to have a seizure caused by fever. Ask your doctor for more information. Tell your doctor if a child who is getting flu vaccine has ever had a seizure.

Problems that could happen after any injected vaccine:

  • People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
  • Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.
  • Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the vaccine safety website:  http://www.cdc.gov/vaccinesafety/index.html.

Digital Copy of Flu Background Flyer