The status of P. falciparum resistance to chloroquine in Sabah, Malaysia were not know until 1971-1972. Several in-vivo and on in-vivo studies were conducted from 971-1975, and the result showed 51% out of total 57 cases studied were resistant to chloroquine. The latest in-vitro study (collaborative with WHO) started in July 1978, to continue till 1980, to cover the whole State. The preliminary result shows 65 cases (85%) out of a total 76 successful tests are resistant to chloroquine. On the basis of this preliminary result, the radical treatment for P. falciparum infection was changed from chloroquine to Fansidar from June 1979 throughout the State.
PIP: The status of Plasmodium falciparum resistance to chloroquine in Sabah, Malaysia was not known until 1971-72. In 1974 resurgence of malaria was 77% over the number of cases in 1973 despite a malaria control program. Several in-vivo studies and 1 in-vitro study were conducted from 1971-5 and showed 51% out of 57 cases were resitant to chloroquine, the substance most widely used in the control program. 1 study was started in 1978 to continue to 1980; the preliminary results show 65 cases (85%) out of 76 successful tests are chloroquine-resistant. A decision was made to change to Fansidar for treatment of P. falciparum infection and to make other changes in the anti-malaria campaign in 1978-79 such as switching to emulsion concentrate for DDT insecticide spraying and monthly mass drug administration in serious transmission areas.