This week WAidid suggests a recent study from The New England Journal of Medicine (07/21/16) that tried to identify the immune responses induced by a multicomponent meningococcal serogroup B vaccine

SUMMARY:
In the United States, meningococcal disease, caused primarily by Neisseria meningitidis serogroups B, C, and Y, presents a substantial threat to public health. The prevention of serogroup B disease has presented particular challenges. Between 2009 and 2015, seven meningococcal B outbreaks occurred at U.S. Universities. No meningococcal B vaccine was licensed in the United States at that time, although the multicomponent meningococcal serogroup B (4CMenB) vaccine, Bexsero, was licensed elsewhere.
The vaccine was offered to nearly 6000 students, beginning in December 2013. Within 6 months, 95% of eligible students had received at least one dose and 89% had completed the two-dose series.
The authors  conducted a seroprevalence survey among students to assess vaccination status and collect serum specimens to quantify titers of serum bactericidal antibodies (SBA) with an assay that included human complement (hSBA). They compared the proportion of vaccinated and unvaccinated participants who were seropositive for the outbreak strain and for one closely related reference strain (44/76-SL, which included fHbp) and one mismatched reference strain (5/99, which included neisserial adhesin A), both of which were used in vaccine development. Seropositivity was defined as an hSBA titer of 4 or higher.
Eight weeks after the second dose of the 4CMenB vaccine was administered, there was no evidence of an hSBA response against the outbreak strain in 33.9% of vaccines, although no cases of meningococcal disease caused by N. meningitidis B were reported among vaccinated students.

AUTHORS: Nicole E. Basta, Adel A.F. Mahmoud, Julian Wolfson, Alexander Ploss, Brigitte L. Heller, Sarah Hanna, Peter Johnsen, Robin Izzo, Bryan T. Grenfell, Jamie Findlow, Xilian Bai, Ray Borrow.

To read the abrstract online click HERE