The Centers for Disease Control and Prevention (CDC) convened a Working Group in October 1995 to summarize the data regarding the risk of invasive group A streptococcal (GAS) disease among household contacts of an index patient and the potential efficacy of chemoprophylaxis. This statement on chemoprophylaxis for prevention of subsequent cases among household contacts is intended for use by public health professionals and clinicians. The CDC invited representatives of the American Academy of Pediatrics, the Council of State and Territorial Epidemiologists, the Hospital Infection Control Practice Advisory Committee, the Infectious Diseases Society of America, and experts from academia to participate. Data on the transmission of GAS and risk factors for severe infection were considered. Population-based surveillance data were used to estimate the risk of invasive GAS disease among household contacts of a case patient. The potential efficacy of chemoprophylaxis was considered using estimates of the efficacy of various regimens in eradicating pharyngeal carriage. This document summarizes the data considered by the Working Group to develop its position. The consensus achieved by group discussion at the meeting was incorporated in a draft document, which was reviewed by all members and revised to include suggested changes. The Working Group concluded that no definite recommendations can be made at this time regarding chemoprophylaxis for household contacts of persons with invasive GAS infection. More data are needed to assess the risk of subsequent cases and to determine an optimal regimen for chemoprophylaxis. Until such data are available, physicians and health departments should base decisions regarding chemoprophylaxis on their assessment of the risk associated with each individual case.
