Malnutrition predisposes infection. Meningitis, including Haemophilus influenzae type B, is common in Africa and Southeast Asia where malnutrition is rampant. This disease has a high incidence in Alaskan eskimos where malnutrition is a problem. H. influenzae meningitis incidence is also highly correlated with low socioeconomic status in the United States. Meningitis is one of the most serious infectious diseases seen in children in the United States and incidence rates are increasing. A poor nutritional status and the lack of breast feeding have been suggested as risk factors. Because there is no efficacious vaccine available, the elucidation of risk factors is important in designing preventative health measures. A second question in need of investigation is the nutritional penalty of the disease. Treatment of the disease routinely involves starving infants for 7-10 days during the stress of infection and ongoing brain growth. We propose to examine certain nutritional risk factors involved in acquisition of, and the nutritional penalty incurred by H. influenzae meningitis. All cases of H. influenzae meningitis admitted to Children's Orthopedic Hospital and Medical Center between Dec. 1, 1983 to Nov. 30, 1986, will be studied. Approximately 200 subjects will be enrolled, 180 will complete the study. Siblings (less than 10 yr old) and controls from the case's pediatrician's practice will be used for comparison groups. Admission nutritional status will be assessed by measuring height, weight, mid-arm circumference, triceps fat fold and hair zinc. To supplement this information, birth weight, growth histories, breast feeding history, the use of drugs and vitamin or mineral supplements and qualitative dietary intakes will be recorded. The nutritional penalty for the cases will be determined by collecting the following data at admission and every fifth day of hospital stay: weight, mid-arm circumference, triceps fat fold, and serum content of pre-albumin, erythrocyte glutathione reductase activity, and protoporphyrin/heme ratio. Daily body temperatures and calorie counts will be taken. Follow-up assessments of nutritional status will be made at 1, 3, and 6 months post disease. Data from this research will allow the design of preventative health care measures for the disease. Also, better care can be implemented if the nutritional penalty is known.