Update: Guillain-Barré syndrome among recipients of Menactra meningococcal conjugate vaccine--United States, October 2005-February 2006.

In October 2005, a possible association between Guillain-Barré Syndrome (GBS) and receipt of meningococcal conjugate vaccine (i.e., meningococcal polysaccharide diphtheria toxoid conjugate vaccine [Menactra]) (MCV4) was reported. GBS is a serious neurologic disorder involving inflammatory demyelination of the peripheral nerves. At the time of the first report, five confirmed cases of GBS after receipt of MCV4 had been reported to the Vaccine Adverse Events Reporting System (VAERS). During the 4 months since, three additional confirmed cases of GBS have been reported. This report describes two of these recent cases and provides additional data collected through February 2006. Because available evidence neither proves nor disproves a causal relation between MCV4 and GBS, further monitoring and studies are ongoing within VAERS and the Vaccine Safety Datalink (VSD). CDC continues to recommend use of MCV4 for persons for whom vaccination is indicated; the additional reported cases have not resulted in any change to that recommendation.