Quadrivalent meningococcal vaccines: hyporesponsiveness as an important consideration when choosing between the use of conjugate vaccine or polysaccharide vaccine.

Regional variations in the incidence and the distribution of serogroups which are responsible of meningococcal disease necessitate multivalent vaccines to ensure broad coverage for travelers. For almost 30 years, this has been provided by quadrivalent polysaccharide vaccine to protect against serogroups A, C, W-135 and Y, but with the advent of quadrivalent conjugate vaccines is there still a case to use the polysaccharide? The well documented hyporesponsiveness induced by polysaccharide vaccines after repeated administration, most clearly observed against serogroup C, suggest that, where available, conjugate vaccines should always be considered ahead of polysaccharide vaccine.