Two vivax malaria cases detected in Korea.

On June and July 1994, two cases of vivax malaria were consecutively diagnosed at the Yongsan Hospital, Chung-Ang University in Seoul. The first patient was a soldier serving in western parts of the demilitarized zone (DMZ) while the second case was a resident of a village near DMZ. Neither patients had history of being abroad. Republic of Korea (ROK) has been free of malaria since the mid-1970s except for imported cases. The two vivax malaria cases, together with an additional patient detected in 1993, occurred in relatively small areas near DMZ. This necessitated an epidemiologic surveillance. When medical records and blood smears in the areas were examined, no other cases were found. Of 7,723 mosquitoes collected by a black light trap for two nights in June, 7,066 (91.5%) were Anopheles sinensis. In order to evaluate a significance of the recent malaria occurrence, a surveillance system should be operated in the areas.