FDA, CDC Update Alert on Guillain-Barré Syndrome Tied to MCV4

FDA and CDC officials recently updated a health advisory issued last fall that concerned reports of Guillain-Barré syndrome, or GBS, associated with administration of tetravalent meningococcal conjugate vaccine, or MCV4. Federal health officials say they are continuing to investigate the situation but, at this time, have announced no changes to current recommendations regarding MCV4 immunization.

As of Sept. 22, HHS' Vaccine Adverse Event Reporting System had received reports of 17 confirmed cases of GBS among patients ages 11 to 19 years that occurred after administration of MCV4. In 15 of those cases, symptoms of GBS were seen within six weeks after the vaccine was given. Two additional case reports of GBS among individuals 20 or older also have been confirmed. All affected individuals are reported to be recovering or have recovered.

In the previous advisory, issued Sept. 30, 2005, a total of five cases of GBS associated with MCV4 immunization were reported.

Although the current case reports suggest an increased risk of GBS after MCV4 immunization, CDC officials noted in an online fact sheet dated Oct. 20 that data limitations preclude establishment of a definitive causal relationship. The CDC's Advisory Committee on Immunization Practices, or ACIP, was scheduled to discuss the cases at its Oct. 25-26 meeting. At this time, no changes in MCV4 immunization recommendations have been announced pursuant to these GBS cases.

Clinicians are encouraged to report suspected cases of GBS associated with MCV4 administration to VAERS online or by calling (800) 822-7967.

Approved in January 2005 to prevent meningococcal infection among 11- to 55-year-olds, MCV4 is manufactured by sanofi pasteur and sold under the brand name Menactra. Early last year, the AAFP adopted recommendations consistent with those of ACIP and the CDC that called for routine MCV4 immunization of most adolescents and others at increased risk for meningococcal disease.

Then, in May of this year, the AAFP joined the CDC and other groups in calling for a temporary deferral of MCV4 immunization among 11- and 12-year-olds until a shortage of Menactra could be resolved. In a recent update from the CDC and sanofi pasteur officials, AAFP staff learned that although the vaccine supply has improved somewhat, that deferral recommendation continues at present.

GBS is a rare but serious neurological disorder that may occur idiopathically or after certain infections. The syndrome is characterized by increasing weakness in leg, arm and other muscles that can be quite debilitating and may require hospitalization. Even so, the disorder typically resolves spontaneously, although some patients may experience residual neurological deficits.