DENGUE-TYPE VIRUSES ISOLATED IN SINGAPORE

A dengue-like illness with marked haemorrhagic manifestations appeared in Singapore in 1960. Its similarity in many respects to the haemorrhagic fevers of Thailand and the Philippines led to its being described as "Singapore haemorrhagic fever".This paper describes the isolation and identification of dengue-type viruses from patients in Singapore between 1960 and 1962. In addition to the conventional complement-fixation and neutralization tests, a new test, called the "sensitized erythrocyte agglutination test", was employed; this test method is described.Altogether 21 dengue-type viruses were isolated, including dengue types 1, 2 and 4. Chikungunya virus, prominent in the Thailand disease, was not detected.The author suggests that study of the epidemiology of haemorrhagic fevers in South-East Asia would cast further light on the transmission of arboviruses.