Pneumococcal disease: the latest on immunisation

In 2005, the WHO estimated that 1.6 million people die of pneumococcal disease every year, including 0.7 to one million children under 5 years of age. Pneumococcal vaccination has been shown to reduce infections with vaccine serotypes by 97%. However, vaccine development is a particular challenge because of the organism’s polysaccharide capsule, which protects it from the primary immune response and is responsible for the large number (90-plus) of serotypes. Further, since the introduction of widespread vaccination, there is evidence that vaccine serotypes are being replaced among carriers by nonvaccine serotypes. This article describes pneumococcal disease, the pneumococcal vaccines used in Australia, the rationale for their use and future challenges in this ongoing battle.

Picture credit: © Molly Borman Biomedical Illustrations, Inc.