Risk factors for meningococcal disease in Cape Town.

Objective: To determine the risk factors associated with meningococcal disease among children living in Cape Town.

Design: A case-control study was conducted from October 1993 to January 1995.

Setting: The study population consisted of all children under the age of 14 years who were resident in the Cape Town metropolitan region. Cases and controls were selected from Red Cross War Memorial Children's Hospital.

Results: A total of 70 cases and 210 controls were interviewed. Significant risk factors for meningococcal disease included being breast-fed for less than 3 months (adjusted odds ratio (OR) 2.4); overcrowding (adjusted OR 2.3); and age less than 4 years (adjusted OR 2.3). Exposure to two or more household members who smoked was also a risk factor, but only in the presence of a recent upper respiratory tract infection (adjusted OR 5.0).

Conclusion: This is the first case-control study in South Africa examining risk factors for meningococcal disease. It provides further evidence for reduction of smoking, reduction of overcrowding and promotion of breast-feeding as important public health measures.