Primaquine-chloroquine prophylaxis against malaria in Southeast-Asian refugees entering South Australia.

In 1980, the incidence of malaria among Southeast-Asian refugees arriving in South Australia rose substantially to 22.0 cases/1000 arrivals. All these cases were caused by Plasmodium vivax, and the majority occurred in the small proportion of refugees who had arrived by way of Indonesian camps of asylum (59.2 cases/1000 arrivals). The commencement of an eight-week prophylactic regimen with primaquine (22.5 mg/week) and chloroquine (300 mg/week; 600 mg first dose) by 1388 refugees proved significantly effective in reducing the incidence of malaria among this population. The regimen was administered without the assessment of glucose-6-phosphate dehydrogenase levels, and a transient haemoglobinuria occurred in only one refugee. Other side-effects were minimal when the administration of drugs was delayed until several days after the arrival of the refugee in Australia.