ACUTE HEMORRHAGIC CONJUNCTIVITIS: A MIXED VIRUS OUTBREAK AMONG VIETNAMESE REFUGEES ON GUAM

In May 1975 the authors investigated an outbreak of acute hemorrhagic conjunctivitis that affected an estimated 29,000 refugees from South Vietnam who stayed on Guam while en route to the United States. Illness usually lasted 6–10 days and was characterized by conjunctival injection (100%), lid edema (84%), eye irritation (81%) and subconjunctival hemorrhages (45%). Conjunctival swabs and paired serum specimens on a limited number of patients implicated enterovirus 70 as a major etiologic agent and adenovirus 11 as a less frequent agent. Adenovirus 8 and herpes simplex virus caused concurrent, sporadic cases of keratoconjunctivitis. Forty-three per cent of the refugees in a sample of 604 refugees were affected, and the attack rate was highest on evacuation vessels where crowding and poor sanitation facilitated person-to-person spread of infection. Because the outbreak subsided on Guam, and because infection was transmitted there to only 13 of about 1300 Americans in frequent contact with affected refugees, the risk of secondary outbreaks in the United States appeared small.