A cluster of cases of Reye syndrome associated with chickenpox.

In the spring of 1980, four confirmed, and three possible cases of Reye syndrome, each associated with a chickenpox prodromal illness, were identified in Las Cruces, NM. One patient, a 5-year-old girl, died. Cases tended to occur in one section of the community, among children attending two of the 16 elementary schools. A telephone survey of parents with school-aged children (6 to 9 years old) suggested that a significantly greater attack rate of chickenpox occurred in children attending those two schools. Based upon this survey and the expected distribution of chickenpox among children less than 15 years of age, the incidence of Reye syndrome following chickenpox infection in the county in which Las Cruces is located was estimated to be 2.5/10,000 cases of chickenpox; these data reveal a four- to ninefold greater incidence of Reye syndrome than that following influenza B infections, which was previously estimated based upon a cluster of five cases in a county in Michigan. Additional investigations of Reye syndrome clusters are needed in an effort to identify and study suspected risk factors and to better define the relationship between Reye syndrome and viral infections.