The long term goal of this project is to translate in vitro and clinical findings about Tropical Infectious Diseases into the in vivo realities of impoverished Brazilian families who suffer their deadly consequences. By defining the lay language of severe childhood illness and its correlation with biomedical disease categories, medical advances aimed at reducing the staggering infant/childhood mortality in Northeast Brazil can be applied and made understood at the household/community level. The research design combines 1.) qualitative anthropological interview methods involving the elicitation and analysis of illness explanatory models from village traditional healers, impoverished mothers, and Brazilian physicians; 2.) epidemiologic investigation of retrospective and terminal illness episodes at the community level; 3.) a case control study of 50 hospitalized pediatric "Illness of The Child" patients; and 4.) implementation of a high risk identification and referral system in University of Fortaleza at Ceara's primary health care program and evaluation of its impact on reducing mortality due to "Illness of The Child".