Risk factors for meningococcal meningitis in northern Ghana

Meningococcal meningitis is a major cause of morbidity and mortality in the meningitis belt of sub-Saharan Africa where it occurs in epidemics every 8-12 years. Risk factors for the disease in this setting remain largely unknown. We carried out a case-control study to investigate possible risk factors among survivors of a meningitis epidemic occurring in 1997 in northern Ghana. A structured questionnaire on socio-economic factors, housing and household overcrowding, smoking and exposure to smoke and close contact with a case was administered to 505 of the survivors and 505 of age-, sex- and location-matched controls. Cooking in kitchens with firewood stoves (OR 9.00, CI 1.25-395) and sharing a bedroom with a case (OR 2.18 CI 1.43-3.4) were found to be risk factors for disease. Socio-economic factors, overcrowding, smoking and passive exposure to tobacco smoke were not found to be risk factors. Exposure to smoke from cooking fires or close contact with a case puts people at risk of contracting meningococcal meningitis. In the hot dry months, exposure to smoke from cooking fires should be minimized by encouraging alternatives to cooking over wood fires, or cooking outside. If wood-burning stoves cannot be avoided, kitchens should be made larger with improved ventilation. Meningitis cases should be nursed in well-ventilated rooms and the number of people sharing a room with a case kept at a minimum.