Resurgence of the Malaria Vivax Cases in Korea

Shim, Jae Chul; Kim, Dae Seong

Abstract

Vivax malaria, which was once thought to be eradicable since more than 20 years ago, has made a dramatic resurgence since 1993 in the northern parts of Kyeonggi-do in the background of 0.13 of the annual parasite incidence in the population of 956,773 and 2 positives (0.07%) of asymptomatic parasitaemia among the 2,937 residents of mass blood survey in the area in 1969. The majority of the cases were soldiers infected in several counties located within 5 km from the Demilitarized Zone (DMZ) in 1994. Since then, malaria cases have increased and have tended to expand toward eastern and southern areas. Korean malaria is characterized by asymptomatic parasitaemia with long prepatent period, so malaria cases, including those manifesting as general fever should be treated with a combination of chloroquine and pyrimethamine to prevent the completion of sporogonic cycle in the mosquitoes. For the most effective control of vector mosquitoes, residual insecticides should be applied in the military houses and animal shelters with thermal fogging, including the control of the pre-stages of physiological age of the mosquitoes within 25 km from the DMZ. It is strongly suggested that military uniforms be treated with 0.5% permethrin complex (permethrin 39%+cyfluthrin 1%) or permethrin formulation. Further genetic studies are desired to determine the subspecies of Plasmodium vivax because Korean strain of malaria is likely to be a complex form of Plasmodium vivax vivax and Plasmodium vivax hibernans.