Abstract. The sensitivity of Plasmodium falciparum infections to pyrimethamine-sulfadoxine was studied in 18 Indonesian patients in Jayapura, Irian Jaya. In 16 of the 18 patients parasitaemia was cleared by day 6 and the patients remained without parasitaemia through day 28. Two of the 18 patients had late recrudescences consistent with RI-type resistance; one each on days 14 and 21. Pyrimethaminesulfadoxine is still an effective antimalarial for most patients with falciparum malaria in Jayapura.
