FAQs About the H1N1 Flu Vaccine
Click on any of the questions below for answers to frequently asked questions about the H1N1 flu vaccine at Lake Forest Hospital.
- What are the risks from 2009 H1N1 influenza vaccine?
- Will the seasonal flu vaccine also protect against the 2009 H1N1 flu?
- Can the seasonal vaccine and the 2009 H1N1 vaccine be given at the same time?
- Who will be recommended to receive the 2009 H1N1 vaccine?
- Do those that have been previously vaccinated against the 1976 swine influenza need to get vaccinated against the 2009 H1N1 influenza?
- Will this vaccine be made differently than the seasonal influenza vaccine?
- Are there other ways to prevent the spread of illness?
- Will two doses of vaccine be required?
- What will be the recommended interval between the first and second dose for children 9 years of age and under?
- Will the 2009 H1N1 influenza vaccines be safe?
- Are there any side effects to the 2009 H1N1 influenza vaccine?
- Are there some people who should not receive this vaccine?
- How will the 2009 H1N1 influenza vaccines be monitored for safety?
- Will the 2009 H1N1 vaccines that are currently recommended contain adjuvants?
- Will the 2009 H1N1 influenza vaccine contain thimerosal?
- Will the benefits of the 2009 H1N1 influenza vaccines outweigh the risks? Is this something I should talk to my healthcare provider about?
- Will there be a possibility of Guillain-Barré Syndrome (GBS) cases following the 2009 H1N1 vaccine?
- What is the best source of information for 2009 H1N1 influenza vaccine safety?
- What is Guillain-Barré syndrome (GBS)?
- What causes GBS?
- Who is at risk for developing GBS?
- Do vaccines cause GBS?
- How common is GBS, and how common is it after people are vaccinated for seasonal influenza?
- What happened in 1976 with GBS and the swine flu vaccine?
- Why did some people develop GBS after they received the 1976 swine flu vaccine?
- Do you expect that the 2009 H1N1 vaccine will be associated with GBS?
- How will public health authorities investigate cases of GBS?
- How will the federal government determine whether people who receive the 2009 H1N1 vaccine have an increased risk for GBS?
Q: What are the risks from 2009 H1N1 influenza vaccine?
A: A vaccine, like any medicine, could cause a problem, such as a severe allergic reaction. But the risk of any vaccine causing serious harm, or death, is extremely small. The virus in inactivated 2009 H1N1 vaccine has been killed, so you cannot get influenza from the vaccine. The risks from inactivated 2009 H1N1 vaccine are similar to those from seasonal inactivated flu vaccine:
Mild problems:
- Soreness, redness, tenderness, or swelling where the shot was given
- Fainting (mainly adolescents)
- Headache, muscle aches
- Fever
- Nausea
If these problems occur, they usually begin soon after the shot and last 1-2 days.
Severe problems:
- Life-threatening allergic reactions to vaccines are very rare. If they do occur, it is usually within a few minutes to a few hours after the shot.
- In 1976, an earlier type of swine flu vaccine was associated with cases of Guillain-Barré Syndrome (GBS). Since then, flu vaccines have not been clearly linked to GBS.
Q: Will the seasonal flu vaccine also protect against the 2009 H1N1 flu?
A: The seasonal flu vaccine is not expected to protect against the 2009 H1N1 flu.
Q: Can the seasonal vaccine and the 2009 H1N1 vaccine be given at the same time?
A: Inactivated 2009 H1N1 vaccine can be administered at the same visit as any other vaccine, including pneumococcal polysaccharide vaccine. Live 2009 H1N1 vaccine can be administered at the same visit as any other live or inactivated vaccine except seasonal live attenuated influenza vaccine.
Q: Who will be recommended to receive the 2009 H1N1 vaccine?
A: CDC’s Advisory Committee on Immunization Practices (ACIP) has recommended that certain groups of the population receive the 2009 H1N1 vaccine when it first becomes available. These target groups include pregnant women, people who live with or care for children younger than 6 months of age, healthcare and emergency medical services personnel, persons between the ages of 6 months and 24 years old, and people ages of 25 through 64 years of age who are at higher risk for 2009 H1N1 because of chronic health disorders or compromised immune systems.
We do not expect that there will be a shortage of 2009 H1N1 vaccine, but availability and demand can be unpredictable. There is some possibility that initially the vaccine will be available in limited quantities. In this setting, the committee recommended that the following groups receive the vaccine before others: pregnant women, people who live with or care for children younger than 6 months of age, health care and emergency medical services personnel with direct patient contact, children 6 months through 4 years of age, and children 5 through 18 years of age who have chronic medical conditions.
The committee recognized the need to assess supply and demand issues at the local level. The committee further recommended that once the demand for vaccine for these target groups has been met at the local level, programs and providers should begin vaccinating everyone from ages 25 through 64 years. Current studies indicate the risk for infection among persons age 65 or older is less than the risk for younger age groups. Therefore, as vaccine supply and demand for vaccine among younger age groups is being met, programs and providers should offer vaccination to people over the age of 65.
Q: Do those that have been previously vaccinated against the 1976 swine influenza need to get vaccinated against the 2009 H1N1 influenza?
A: The 1976 swine flu virus and the 2009 H1N1 virus are different enough that its unlikely a person vaccinated in 1976 will have full protection from the 2009 H1N1. People vaccinated in 1976 should still be given the 2009 H1N1 vaccine.
Q: Will this vaccine be made differently than the seasonal influenza vaccine?
A: No. This vaccine will be made using the same processes and facilities that are used to make the currently licensed seasonal influenza vaccines.
Q: Are there other ways to prevent the spread of illness?
A: Take everyday actions to stay healthy:
- Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
- Wash your hands often with soap and water, especially after you cough or sneeze. If soap and water are not available, use an alcohol-based hand rub.
- Avoid touching your eyes, nose or mouth. Germs spread that way.
- Stay home if you get sick. CDC recommends that you stay home from work or school and limit contact with others to keep from infecting them.
Q: Will two doses of vaccine be required?
A: The U.S. Food and Drug Administration (FDA) has approved the use of one dose of 2009 H1N1 flu vaccine for persons 10 years of age and older. This is slightly different from CDC’s recommendations for seasonal influenza vaccination which states that children younger than 9 who are being vaccinated against influenza for the first time need to receive two doses. Infants younger than 6 months of age are too young to get the 2009 H1N1 and seasonal flu vaccines.
Q: What will be the recommended interval between the first and second dose for children 9 years of age and under?
A: CDC recommends that the two doses of 2009 H1N1 vaccine be separated by 4 weeks. However, if the second dose is separated from the first dose by at least 21 days, the second dose can be considered valid.
Q: Will the 2009 H1N1 influenza vaccines be safe?
A: We expect the 2009 H1N1 influenza vaccine to have a similar safety profile as seasonal flu vaccines, which have a very good safety track record. Over the years, hundreds of millions of Americans have received seasonal flu vaccines. The most common side effects following flu vaccinations are mild, such as soreness, redness, tenderness or swelling where the shot was given.
The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) will be closely monitoring for any signs that the vaccine is causing unexpected adverse events and we will work with state and local health officials to investigate any unusual events.
Q: Are there any side effects to the 2009 H1N1 influenza vaccine?
A: CDC expects that any side effects following vaccination with the 2009 H1N1 influenza vaccine would be rare. If side effects occur, they will likely be similar to those experienced following seasonal influenza vaccine.
Mild problems that may be experienced include soreness, redness, or swelling where the shot was given, fainting (mainly adolescents), headache, muscle aches, fever, and nausea. If these problems occur, they usually begin soon after the shot and last 1-2 days. Life-threatening allergic reactions to vaccines are very rare. If they do occur, it is usually within a few minutes to a few hours after the shot is given.
After vaccination you should look for any unusual condition, such as a high fever or behavior changes. Signs of a serious allergic reaction can include difficulty breathing, hoarseness or wheezing, swelling around the eyes or lips, hives, paleness, weakness, a fast heart beat or dizziness.
If any unusual condition occurs following vaccination, seek medical attention right away. Tell your doctor what happened, the date and time it happened, and when the vaccination was given. Ask your doctor, nurse, or health department to report the reaction by filing a Vaccine Adverse Event Reporting System (VAERS) form. Or you can file this report yourself through the VAERS Web site at vaers.hhs.gov. You may call 1-800-822-7967 to receive a copy of the VAERS form. VAERS is not able to provide medical advice.
A complete list of possible side effects from both the flu shot and the nasal spray (LAIV or Flu Mist) vaccines are below:
The flu shot: The viruses in the flu shot are killed (inactivated), so you cannot get the flu from a flu shot. Some minor side effects that could occur are:
- Soreness, redness, or swelling where the shot was given
- Fever (low grade)
- Aches
- Nausea
If these problems occur, they begin soon after the shot and usually last 1 to 2 days. Almost all people who receive influenza vaccine have no serious problems from it. However, on rare occasions, flu vaccination can cause serious problems, such as severe allergic reactions. A federal program has been created to help pay for the medical care and other specific expenses of certain persons who have a serious reaction to this vaccine. For more information about this program, call 1-888-275-4772 or visit the program’s website.
The nasal spray (also called LAIV): The viruses in the nasal-spray vaccine are weakened and do not cause severe symptoms often associated with influenza illness. (In clinical studies, transmission of vaccine viruses to close contacts has occurred only rarely.)
In children, side effects from LAIV can include:
- Runny nose
- Wheezing
- Headache
- Vomiting
- Muscle aches
- Fever
In adults, side effects from LAIV can include
- Runny nose
- Headache
- Sore throat
- Cough
Q: Are there some people who should not receive this vaccine?
A: People who have a severe (life-threatening) allergy to chicken eggs or to any other substance in the vaccine should not be vaccinated.
Q: How will the 2009 H1N1 influenza vaccines be monitored for safety?
A: The CDC and FDA closely monitor the safety of seasonal influenza and other vaccines licensed for use in the United States in cooperation with state and local health departments, healthcare providers, and other partners.
The purpose of vaccine safety monitoring is timely identification of clinically significant adverse events following immunization that may be of public health concern. Adverse events, or possible side effects, following immunization may be coincidental to (meaning occurring around the same time but not related to vaccination) or caused by vaccination. The purpose of vaccine safety monitoring is timely identification of clinically significant adverse events following immunization that might be of public health concern.
CDC and its partners will use multiple systems to monitor the safety of 2009 H1N1 influenza vaccine. Two of the primary systems that will be used to monitor the safety of these vaccines after they are in widespread use are: the Vaccine Adverse Event Reporting System (VAERS), which is jointly operated with FDA, and the Vaccine Safety Datalink (VSD) Project.
- Vaccine Adverse Event Report System (VAERS). VAERS is a national program managed by both CDC and FDA to monitor the safety of all vaccines licensed in the United States. Healthcare providers are encouraged to voluntarily report possible adverse events of concern after vaccination, even if they are not certain that the vaccine caused the event. Anyone can file a VAERS report. VAERS relies on information included in these reports to monitor for clinically serious adverse events or health problems that follow vaccination.
Generally, VAERS cannot determine if an adverse event was caused by a vaccine but can help determine if further investigations are needed. FDA and CDC use VAERS data to help identify potential clinically serious vaccine adverse events or health outcomes. If concerns are identified in VAERS, usually further investigation is needed. One important system used to further evaluate concerns identified in VAERS is the Vaccine Safety Datalink (VSD) Project.
- Vaccine Safety Datalink (VSD) Project. The VSD Project is a vaccine safety system used to both identify and confirm adverse outcomes after immunization. This project is a collaboration between CDC and eight large managed care organizations (MCOs), in which comprehensive medical information is collected on approximately 9 million people. The VSD project monitors their data weekly for certain adverse events that could be associated with newly licensed vaccines. VSD conducts studies of vaccine safety adverse events and health outcomes that may arise with any vaccine.
Additionally, CDC will work with numerous partners including other federal agencies, state and local health departments, professional organizations, and academic institutions to actively follow individuals after vaccination to monitor for any potential adverse events.
Q: Will the 2009 H1N1 vaccines that are currently recommended contain adjuvants?
A: No. According to current federal plans, only unadjuvanted vaccines will be used in the United States during the 2009 flu season. This includes all of the 2009 H1N1 and seasonal influenza vaccines that will be available for children and adults in both the injectable and nasal spray formulations. None of these influenza vaccines will contain adjuvants.
2009 H1N1 vaccines with adjuvants are being studied to determine if they are safe and effective. Experts will review these data when they are available. There is no plan at this time to recommend a 2009 H1N1 influenza vaccine with an adjuvant.
Q: Will the 2009 H1N1 influenza vaccine contain thimerosal?
A: The 2009 H1N1 influenza vaccines that FDA is licensing (approving) will be manufactured in several formulations. Some will come in multi-dose vials and will contain thimerosal as a preservative. Multi-dose vials of seasonal influenza vaccine also contain thimerosal to prevent potential contamination after the vial is opened.
Some 2009 H1N1 influenza vaccines will be available in single-dose units, which will not require the use of thimerosal as a preservative.
In addition, the live-attenuated version of the vaccine, which is administered intranasally (through the nose), is produced in single-units and will not contain thimerosal.
Q: Will the benefits of the 2009 H1N1 influenza vaccines outweigh the risks? Is this something I should talk to my healthcare provider about?
A: Currently the 2009 H1N1 influenza virus (sometimes called “swine flu”) seems to be causing serious health outcomes for: 1. healthy young people from birth through age 24; 2. pregnant women; and 3. adults 25 to 64 who have underlying medical conditions.
Seasonal influenza vaccines are highly effective in preventing influenza disease. The expectation is that a vaccine against 2009 H1N1 influenza would probably work in a similar fashion to the seasonal influenza vaccines. CDC and FDA believe that the benefits of vaccination with the 2009 H1N1 influenza vaccine will far outweigh the risks.
Vaccination is the best way to prevent influenza infection and its complications. This is the reason that CDC, national health organizations, and healthcare providers intensively promote vaccination for seasonal influenza, and the reason why so much work is being done to have a vaccine available in the fall for the 2009 H1N1 influenza virus.
Influenza vaccines do not protect against other viruses that cause respiratory illnesses. Even after you are vaccinated, it is still important to wash your hands well and often, to cover your coughs and sneezes, and to stay home if you are sick.
CDC and FDA encourage you to ask your healthcare provider any questions you may have about the 2009 H1N1 influenza vaccine and the seasonal influenza vaccines that will be available during the 2009-2010 influenza season. Your healthcare provider is an excellent source for information on the benefits and risks of vaccination for protection against 2009 H1N1 influenza for you, your children, and other family members.
CDC is working continuously to provide the public with the most current information about 2009 H1N1 influenza and the 2009 H1N1 influenza vaccine and its safety.
Q: Will there be a possibility of Guillain-Barré Syndrome (GBS) cases following the 2009 H1N1 vaccine?
A: Guillain-Barré syndrome (GBS) is a rare disease in which the body damages its own nerve cells, causing muscle weakness and sometimes paralysis. It is not fully understood why some people develop GBS, but it is believed that stimulation of the body’s immune system may play a role in its development. Infection with the bacterium Campylobacter jejuni, which can cause diarrhea, is one of the most common risk factors for GBS. People can also develop GBS after having the flu or other infections (such as cytomegalovirus and Epstein Barr virus). On very rare occasions, they may develop GBS in the days or weeks following receiving a vaccination.
In 1976, there was a small risk of GBS following influenza (swine flu) vaccination (approximately 1 additional case per 100,000 people who received the swine flu vaccine). That number of GBS cases was slightly higher than what is normally seen in the population, whether or not people were vaccinated. Since then, numerous studies have been done to evaluate if other flu vaccines were associated with GBS. In most studies, no association was found, but two studies suggested that approximately 1 additional person out of 1 million vaccinated people may be at risk for GBS associated with the seasonal influenza vaccine. FDA and CDC will be closely monitoring reports of serious problems following the 2009 H1N1 influenza vaccines, including GBS.
Q: What is the best source of information for 2009 H1N1 influenza vaccine safety?
In addition to talking openly with your healthcare providers, CDC also encourages you to stay informed by checking the following Web sites often for the most up-to-date news and information: cdc.gov/H1N1flu and flu.gov.
Q: What is Guillain-Barré syndrome (GBS)?
A: Guillain-Barré syndrome (GBS) is a rare disorder in which a person’s own immune system damages the nerve cells, causing muscle weakness and sometimes paralysis. GBS can cause symptoms that last for a few weeks or several months. Most people recover fully from GBS, but some people have permanent nerve damage.
In rare cases, people have died of GBS, usually from difficulty with breathing. In the United States, for example, an estimated 3,000 to 6,000 people develop GBS each year on average, whether or not they received a vaccination. This is about 1 to 2 cases of GBS per 100,000 people.
Q: What causes GBS?
A: Scientists do not fully understand what causes GBS, but it is believed that stimulation of the body’s immune system may play a role in its development. Here’s what scientists know for sure: About two-thirds of people who develop GBS symptoms do so several days or weeks after they have been sick with a diarrheal or respiratory illness. Infection with the bacterium Campylobacter jejuni is one of the most common risk factors for GBS. People can also develop GBS after having the flu or other infections (such as cytomegalovirus and Epstein Barr virus). On very rare occasions, they may develop GBS in the days or weeks following receiving a vaccination.
Q: Who is at risk for developing GBS?
A: Anyone can develop GBS, but it is more common among adults than children. The incidence of GBS increases with age, and people over age 50 are at greatest risk for developing GBS. Each year, on average, about 3,000 to 6,000 people in the United States develop GBS whether or not they received a vaccination – that’s 1 to 2 people out of every 100,000 people.
Q: Do vaccines cause GBS?
A: It is not fully understood why some people develop GBS, but it is believed that the nerve cells are damaged by a person’s own immune system. Many types of infections, and in very rare cases vaccines, may activate the immune system to cause damage to the nerve cells.
Q: How common is GBS, and how common is it after people are vaccinated for seasonal influenza?
A: GBS is rare. Each year, about 3,000 to 6,000 people in the United States develop GBS whether or not they received a vaccination – that’s 1 to 2 people out of every 100,000 people. This is referred to as the background rate.
In 1976, there was a small risk of GBS following influenza (swine flu) vaccination (approximately 1 additional case per 100,000 people who received the swine flu vaccine). That number of GBS cases was slightly higher than the background rate for GBS.
Since then, numerous studies have been done to evaluate if other flu vaccines were associated with GBS. In most studies, no association was found, but two studies suggested that approximately 1 additional person out of 1 million vaccinated people may be at risk for GBS associated with the seasonal influenza vaccine. It is important to keep in mind that severe illness and possible death can be associated with influenza, and vaccination is the best way to prevent influenza infection and its complications.
Q: What happened in 1976 with GBS and the swine flu vaccine?
A: Scientists first reported a suspected link between GBS and vaccinations in 1976, during a national campaign to vaccinate people against a swine flu virus. The investigation found that vaccine recipients had a higher risk for GBS than those who were not vaccinated (about 1 additional case occurred per 100,000 people vaccinated). Given this association, and the fact that the swine flu disease was limited, the vaccination program was stopped.
Since then, numerous studies have been done to evaluate if other flu vaccines were associated with GBS. In most studies, no association was found, but two studies suggested that approximately 1 additional person out of 1 million vaccinated people may be at risk for GBS associated with the seasonal influenza vaccine.
Q: Why did some people develop GBS after they received the 1976 swine flu vaccine?
A: The Institute of Medicine (IOM) conducted a thorough scientific review in 2003 and concluded that people who received the 1976 swine influenza vaccine had a slight increased risk for developing GBS. Scientists have multiple theories on why this increased risk may have occurred, but the exact reason for this association remains unknown.
Q: Do you expect that the 2009 H1N1 vaccine will be associated with GBS?
A: We expect the 2009 H1N1 vaccine to have a similar safety profile as seasonal flu vaccines, which have very good safety track records. The seasonal influenza vaccine has not been consistently associated with GBS.
Q: How will public health authorities investigate cases of GBS?
A: Ensuring the safety of vaccines is a high priority for CDC. CDC and its partners have an aggressive plan to actively monitor the 2009 H1N1 vaccine to ensure its safety. Several systems are in place to monitor vaccine safety. One of these systems is the Vaccine Adverse Event Reporting System (VAERS).
CDC and FDA co-manage VAERS, which serves as an early warning system to collect voluntary reports about possible side effects that people experience following vaccinations. CDC and FDA scientists review all VAERS reports and store the information in a computerized database that is monitored to detect new, unusual, or rare health events that could be possible side effects of vaccines.
In addition to the normal vaccine safety monitoring systems, CDC is proactively putting additional monitoring systems in place to ensure safety after licensing. Some of these systems include: actively observing persons in defined geographic areas, collaborating with professional organizations for reports of any adverse events after vaccination, and conducting thorough investigations when severe adverse events occur to determine whether they may have been associated with the vaccine. Through these numerous approaches, we will be able to detect any possible risk of GBS that might be associated with the 2009 H1N1 vaccine early in the vaccination campaign and take appropriate action.
Q: How will the federal government determine whether people who receive the 2009 H1N1 vaccine have an increased risk for GBS?
A: GBS cases occur every year in the general population for many different reasons. To monitor whether people who receive the 2009 H1N1 vaccine have an increased risk for GBS, U.S. public health officials will determine if the number of GBS cases reported among people who receive the 2009 H1N1 vaccine is higher than the number of cases reported in the general population.
If there is an increase in the number of reported cases, public health officials will conduct intensive investigations. If any problems are detected with this 2009 H1N1 vaccine, they will be reported to health officials, healthcare providers, and the public, and health officials will take needed action to ensure the public's health and safety.
