A community outbreak of meningococcal serogroup B disease in western Sydney: the challenges of identification and significance.

The Communicable Diseases Network Australia guidelines provide information for early clinical and public health management of meningococcal disease, including community outbreaks. While community outbreaks of meningococcal serogroup C infections have been reported, community outbreaks of meningococcal serogroup B infections have not been declared in Australia. Three cases of meningococcal serogroup B disease occurred in 2 adjacent suburbs in western Sydney in Spring 2008. Although the temporal and geographic proximity of these cases fulfilled the criteria for a community outbreak, difficulties in establishing an epidemiological or serosubgroup link, and arbitrary definition of the term 'community' provide challenges for identifying such outbreaks. In addition, the declaration of a community outbreak of meningococcal B infection does not provide guidance for the public health response because a vaccine is not available and community-wide prophylaxis is not recommended.