NYS Nurses Association

Influenza Vaccine: Frequently Asked Questions (FAQs)

Introduction: All About the Flu

How can flu be prevented?

The single best way to prevent the flu is to get vaccinated each season. There are two types of flu vaccine:

The "flu shot"–an inactivated vaccine (containing killed virus) that is given with a needle. The seasonal flu shot is approved for use in people 6 months of age and older, including healthy people, people with chronic medical conditions and pregnant women.

The nasal–spray flu vaccine –a vaccine made with live, weakened flu viruses that do not cause the flu (sometimes called LAIV for "Live Attenuated Influenza Vaccine"). LAIV is approved for use in healthy* people 2-49 years of age who are not pregnant.

How soon will the flu vaccine work?

About two weeks after vaccination, antibodies develop that protect against influenza virus infection. Flu vaccines will not protect against flu-like illnesses caused by non-influenza viruses.

What are the components for flu vaccine?

The seasonal flu vaccine protects against the three influenza viruses that research suggests will be most common in a particular season. For example, the 2010-2011 flu vaccine will protect against 2009 H1N1, and two other influenza viruses (an H3N2 virus and an influenza B virus).

When should I get vaccinated against seasonal flu?

Yearly flu vaccination should begin in September, or as soon as vaccine is available, and continue throughout the flu season which can last as late as May. This is because the timing and duration of flu seasons vary. While flu season can begin early as October, most of the time seasonal flu activity peaks in January or later.

Who should get vaccinated?

On February 24, 2010 vaccine experts voted that everyone 6 months and older should get a flu vaccine each year starting with the 2010-2011 influenza season. CDC's Advisory Committee on Immunization Practices (ACIP) voted for "universal" flu vaccination in the U.S. to expand protection against the flu to more people. While everyone should get a flu vaccine each flu season, it’s especially important that certain people get vaccinated either because they are at high risk of having serious flu-related complications or because they live with or care for people at high risk for developing flu-related complications.

Who is at high risk for developing flu-related complications?

Children younger than 5, but especially children younger than 2 years old
Adults 65 years of age and older
Pregnant women
Also, last flu season, American Indians and Alaskan Natives seemed to be at higher risk of flu complications
People who have medical conditions including:
- Asthma (even controlled or mild)
- Neurological and neurodevelopmental conditions [including disorders of the brain, spinal cord, peripheral nerve, and muscle such as cerebral palsy, epilepsy (seizure disorders), stroke, intellectual disability (mental retardation), moderate to severe developmental delay, muscular dystrophy, or spinal cord injury]
- Chronic lung disease (such as chronic obstructive pulmonary disease [COPD] and cystic fibrosis)
- Heart disease (such as congenital heart disease, congestive heart failure and coronary artery disease)
- Blood disorders (such as sickle cell disease)
- Endocrine disorders (such as diabetes mellitus)
- Kidney disorders
- Liver disorders
- Metabolic disorders (such as inherited metabolic disorders and mitochondrial disorders)
- Weakened immune system due to disease or medication (such as people with HIV or AIDS, or cancer, or those on chronic steroids)
- People younger than 19 years of age who are receiving long-term aspirin therapy
- People who are morbidly obese (Body Mass Index [BMI] of 40 or greater)

Who else should get vaccinated?

Other people for whom vaccination is especially important are:
People who live in nursing homes and other long-term care facilities
People who live with or care for those at high risk for complications from flu, including:
- Health care workers
- Household contacts of persons at high risk for complications from the flu
- Household contacts and caregivers of children younger than 5 years of age with particular emphasis on vaccinating contacts of children younger than 6 months of age (children younger than 6 months are at highest risk of flu-related complications but are too young to get vaccinated)

Who can receive the nasal spray seasonal flu vaccine?

Vaccination with the nasal-spray flu vaccine is an option for healthy people 2-49 years of age who are not pregnant. Even people who live with or care for those in a high risk group (including health care workers) can get the nasal-spray flu vaccine as long as they are healthy themselves and are not pregnant. The one exception is health care workers who care for people with severely weakened immune systems who require a protected hospital environment; these people should get the inactivated flu vaccine (flu shot).

Who should not be vaccinated against seasonal flu?

Some people should not be vaccinated without first consulting a physician. They include:

People who have a severe allergy to chicken eggs.
People who have had a severe reaction to an influenza vaccination in the past.
People who developed Guillian-Barré syndrome (GBS) within 6 weeks of getting an influenza vaccine previously.
Children younger than 6 months of age (influenza vaccine is not approved for use in this age group).
People who have a moderate or severe illness with a fever should wait to get vaccinated until their symptoms lessen.

What side effects can I expect from flu vaccine?

Typically, side effects include a slightly swollen or sore arm for 1-2 days. As with any medication, allergic reactions may be seen in a small number of the population. Serious side effects, which are rare, should be reported to the CDC reporting system (VAERS). The VAERS reporting form can be accessed at www.vaers.hhs.gov then fax the form to 1-877-721-0366.

References: The Centers for Disease Control and Prevention, Vaccine Adverse Event Reporting System