Vaccine Safety

Frequently Asked Questions about Guillain-Barré Syndrome and Menactra® Meningococcal Vaccine

Does Menactra Meningococcal Conjugate Vaccine cause Guillain-Barré Syndrome (GBS)?
Why are you making this announcement at this time?
How can I report a case of GBS after Menactra or any vaccine?
What are the risks from meningococcal vaccine?
Why are you continuing to recommend this vaccine?
What is GBS?
What causes GBS?
What are FDA and CDC doing to investigate?
Will any further action be taken?
Are you communicating with the company who makes this vaccine?
Is there another vaccine to protect against this disease?
Have other vaccines ever been suspected of causing GBS?
Where can I get more information about meningococcal vaccines?
Where can I get more information about GBS following Menactra vaccine?

Does Menactra Meningococcal Conjugate Vaccine cause Guillain-Barré Syndrome (GBS)?

No. At this time, we cannot say that Menactra vaccine causes GBS.

Why are you making this announcement at this time?

We are updating the public with new information about a possible but unproven rare risk that GBS could be associated with Menactra Meningococcal Conjugate vaccine. This information was first identified and shared with the public in October 2005. We also want to make people aware of this matter so they will report possible cases of GBS to the Vaccine Adverse Event Reporting System (VAERS).

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How can I report a case of GBS after Menactra or any vaccine?

Because of the potentially serious nature of this matter, CDC and FDA are asking any person with knowledge of any possible cases of GBS occurring after Menactra to report them to the Vaccine Adverse Event Reporting System (VAERS) to help the agencies further evaluate the matter. Individuals can report to VAERS on the web at www.vaers.hhs.gov or by phone at 1-800-822-7967.

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What are the risks from meningococcal vaccine?

A vaccine, like any medicine, could possibly cause serious problems, such as severe allergic reactions. The risk of meningococcal vaccine causing serious harm or death is extremely small.

Mild problems: Up to about half of people who get meningococcal vaccines have mild side effects, such as redness or pain where the shot was given. If these problems occur, they usually last 1 to 2 days. A small percentage of people who receive the vaccine develop a fever.
Severe problems: Serious allergic reactions, within a few minutes to a few hours of the shot, are very rare. A few cases of Guillain-Barré Syndrome, a serious nervous system disorder, have been reported among people who have received Menactra vaccine. There is not enough evidence yet to tell whether any of these cases were caused by the vaccine. This is being investigated by health officials. All persons who have become ill with GBS following Menactra immunization have recovered or are recovering.

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Why are you continuing to recommend this vaccine?

Meningococcal infection, which Menactra prevents, is a major cause of invasive meningococcal disease, affecting approximately 1 in 100,000 people annually. The infection can be life threatening: 10 to 14 percent of cases are fatal, and 11 to 19 percent of survivors may have permanent disability. As we learn more, the benefits and risks of the vaccine will be reassessed.

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What is Guillain-Barré Syndrome?

GBS is a serious, rare neurological disorder that can occur, often in healthy individuals, either spontaneously or after certain infections. GBS typically causes increasing weakness in the legs and arms that can be severe and require hospitalization. People who become ill with GBS usually make a full recovery.

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What causes Guillain-Barré Syndrome?

Many things can cause GBS, including common infections such as sore throats and other infections that occur in the community.

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What are FDA and CDC doing to investigate?

The Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) continue to monitor reports to the Vaccine Adverse Event Reporting System (VAERS) and encourage reporting of any cases of GBS after Menactra to VAERS. CDC's Vaccine Safety Datalink and other databases are being queried to identify any cases of GBS after Menactra. Other types of studies to further evaluate the risk are planned. Because GBS is very rare, scientific study of this issue is challenging and requires extremely large databases. CDC is also communicating with and obtaining input into the investigation from the Advisory Committee on Immunization Practices, the American Academy of Pediatrics, and the National Vaccine Advisory Committee about this investigation.

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Will any further action be taken?

Yes, CDC and FDA will continue to monitor the situation closely. There is not a simple number of cases that would have to be reported before CDC and FDA take additional action. The reason is that GBS can occur in the absence of vaccination, and thus every case needs to be evaluated carefully for possible causes. The timing of GBS following vaccination, clinical factors, and the total number of people vaccinated are important to consider as well. CDC's Advisory Committee on Immunization Practices and other advisory groups will also consider thi8s updated information.

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Are you communicating with the company who makes the vaccine?

Yes, the FDA and CDC are working closely with the vaccine manufacturer, Sanofi Pasteur, Inc., and will continue to do so as we actively investigate the situation.

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Is there another vaccine to protect against this disease?

Yes, there is another meningococcal vaccine that is licensed by the FDA called Menomune®. It has different characteristics and is not recommended for routine use, but only for certain individuals at high risk. It is available in limited supply.

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Have other vaccines ever been suspected of causing GBS?

In 1976, flu vaccine associated with a rare risk of GBS. The Instituted of Medicine Immunization Safety Review Committee recently concluded that the evidence favors acceptance of a causal relationship between 1976 swine influenza and GBS, but the evidence is inadequate to accept or reject a causal relationship between GBS and influenza vaccines administered since then. For more information, see the IOM's report, Immunization Safety Review: Influenza and Neurological Complications. The FDA and CDC continually monitor the safety of influenza vaccine.

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