Acute haemorrhagic conjunctivitis in Hong Kong 1971-1975.

Acute haemorrhagic conjunctivitis occurred in epidemic in Hong Kong in 1971 and 1975 respectively. Two picornaviruses, the Enterovirus type 70 and an antigenic variant of Coxsackie virus type A24, were isolated during the 1971 outbreak, while only the latter virus was detected in the 1975 outbreak. In 1972 and 1974, sporadic cases of conjunctivitis associated with Enterovirus type 70 were observed. Serological survey in late 1975 showed a high proportion of the population might still be susceptible to both viruses. Recrudescence of the disease is conceivable when environmental condition is favourable for the spread of these viruses.