A study in the August 2000 issue of the Archives of Disease in Childhood found that parents who smoke increase the risk of meningococcal meningitis for their children by about 200% for every 20 cigarettes smoked at home on an average day (220% if the mother smokes, 170% if only the father smokes). Meningitis can strike suddenly and without warning. Keeping your kids in a smoke-free environment is one way you help keep them safe -- from this and from other childhood problems ranging from ear infections to SIDS.