Carriage of Neisseria meningitidis in residents and staff at a residential home for elderly people following a case of invasive disease.

A study of the carriage of Neisseria meningitidis among staff and residents of a 'closed community' (a residential home for elderly people) was conducted after a resident developed invasive meningococcal disease. All 39 other residents and 49 staff who worked at the home during the previous seven days were offered a throat swab and 38 residents and 49 staff consented. Two residents (none in the index case's social group) and one staff member were found to be carrying N. meningitidis, all phenotypically distinct from the infecting isolate. Thus, all four individuals carried different organisms and the index case was sporadic. Our findings suggest that residents or staff in long stay residential settings where a sporadic case occurs need not be offered meningococcal prophylaxis unless they fulfil the existing definition of 'close personal contacts' of the case.