Meningitis vaccine booster may stave off waning immunity

The use of a booster dose of 4CMenB, a meningitis B vaccine, may overcome waning immunity induced by infant vaccination, according to a study recently published in the Canadian Medical Association Journal.

The 4CMenB vaccine, which was recently licensed in Europe, previously demonstrated a good immune response in infants, but it was not known how well the response persisted through childhood. A study conducted by the Oxford Vaccine Group found that high antibody levels declined after four doses of the vaccine in the first year of life.

"Experience with other meningococcal vaccines has shown that waning of bactericidal antibody titres was associated with a decline in vaccine effectiveness following infant vaccination with serogroup C meningococcal conjugate vaccines," the study's authors said.

When children received a booster dose at 40 months of age, however, 89 percent to 100 percent of the children had high antibody levels for all but one of the eight meningitis B strains tested.

"Consistent with other vaccines against meningococcal disease, a waning of hSBA titres was observed after infant vaccination with 4CMenB," the authors said. "A booster dose during preschool years was well tolerated."

Children remain at risk for meningitis B infection through their preschool years and even into adolescence.

"If 4CMenB were to be introduced into a routine vaccination schedule, measures such as adequate disease surveillance would be important to determine whether waning of antibodies might influence the effectiveness of a vaccination campaign against this bacterium," the authors said.