Acute hemorrhagic conjunctivitis, Key West, Florida. An assessment of risk factors for introduction of illness into households and secondary spread during the 1981 epidemic.

From August 22 to November 6, 1981, 989 cases of acute hemorrhagic conjunctivitis were identified in Key West, Florida. The outbreak probably began when an infected 12-year-old Key West resident returned from the Bahamas and transmitted the illness to several neighborhood playmates. The rate of illness was highest for school-aged children, and a high proportion of cases occurred among blacks living in two adjacent low-income housing tracts. A telephone survey of persons living in these two tracts showed that the risk for introduction of illness into a household was 3.8 times greater for families with school-aged children. A study of 100 case households showed that black race, living in the two low-income housing tracts, and having a high ratio of family members per bathroom were variables significantly associated with multiple case households. To limit intracommunity spread of illness, symptomatic children were excluded from school for a period of seven days. The number of reported cases steadily decreased after school exclusion was implemented.