Growth retardation, which becomes obvious around seven years of age, has no relationship to reported family income. Prophylactic oral penicillin can decrease morbidity and mortality associate with pneumococcal septicemia. The newborn infant cohort was unique in determining issues related to the natural history of the disease because the information was prospective and has been captured in the database. The complex database permitted an opportunity to determine outcomes, risk factors, and the application of the severity index to determine the spectrum of severity.