Inactivated Influenza Vaccine: What You Need To Know

Updated 8/11/09

1. Why get vaccinated?

Influenza (“flu”) is a contagious disease.

It is caused by the influenza virus, which can be spread by coughing, sneezing, or nasal secretions.

Other illnesses can have the same symptoms and are often mistaken for influenza. But only an illness caused by the influenza virus is really influenza.

Anyone can get influenza, but rates of infection are highest among children. For most people, it lasts only a few days. It can cause:

• fever
• sore throat
• chills
• muscle aches
• cough
• headache
• fatigue

Some people, such as infants, elderly, and those with certain health conditions, can get much sicker. Flu can cause high fever and pneumonia, and make existing medical conditions worse. It can cause diarrhea and seizures in children. On average, 226,000 people are hospitalized every year because of influenza and 36,000 die – mostly elderly. Infl uenza vaccine can prevent influenza.

2. Live, attenuated influenza vaccine - LAIV (nasal spray)

There are two types of seasonal influenza vaccine:

1. Live, attenuated influenza vaccine (LAIV) contains live but attenuated (weakened) influenza prevent annual fl u. They do virus. It is sprayed into the nostrils.
2. Inactivated influenza vaccine, H1N1 influenza. sometimes called the “flu shot,” is given by injection. Inactivated influenza vaccine is described in a separate Vaccine Information Statement.

Influenza viruses are always changing. Because of this, influenza vaccines are updated every year, and an annual vaccination is recommended.

Each year scientists try to match the viruses in the vaccine to those most likely to cause flu that year. When there is a close match the vaccine protects most people from serious influenzarelated illness. But even when there is not a close match, the vaccine provides some protection. Influenza vaccine will not prevent “influenza-like” illnesses caused by other viruses.

It takes up to 2 weeks for protection to develop after the vaccination. Protection lasts up to a year. LAIV does not contain thimerosal or other preservatives.

3. Who can get LAIV?

LAIV is approved for people from 2 through 49 years of age, who are not pregnant and do not have certain health conditions (see #4, below). Influenza vaccination is recommended for people who can spread influenza to others at high risk, such as:

• Household contacts and out-of-home caregivers of children up to 5 years of age, and people 50 and older.
• Physicians and nurses, and family members or anyone else in close contact with people at risk of serious influenza.

Health care providers may also recommend a yearly influenza vaccination for:

• People who provide essential community services.
• People living in dormitories, correctional facilities, or under other crowded conditions, to prevent outbreaks.

Influenza vaccine is also recommended for anyone who wants to reduce the likelihood of becoming ill with influenza or spreading influenza to others.