Immunization Update: Recent Developments And Current Issues

Several recent vaccine developments offer the prospect of improved protection against common bacterial and viral infections. A quadrivalent conjugate meningococcal vaccine approved this year provides increased duration of immunity and the possibility of inducing an immune reaction in children younger than 2 years. Two human-bovine reassortment rotavirus vaccines cause less fever and vomiting than the earlier vaccine and may be less likely to cause viral shedding and intussusception. Widespread use of the 7-valent conjugate pneumococcal vaccine has reduced nasopharyngeal carriage of Streptococcus pneumoniae, as well as invasive disease and acute otitis media caused by this organism. Varicella vaccine has an impressive record of disease reduction, but questions remain regarding the potential use of booster doses and combination with measles-mumps-rubella vaccine.