14th ICID - Poster Abstracts - International Society for Infectious ...

When citing these abstracts please use the following reference:
Author(s) of abstract. Title of abstract [abstract]. Int J Infect Dis 2010;14S1: Abstract number.
Please note that the official publication of the International Journal of Infectious Diseases 2010, Volume 14, Supplement 1
is available electronically on http://www.sciencedirect.com
Final Abstract Number: 29.012
Session: Malaria & Blood-borne Parasites
Date: Wednesday, March 10, 2010
Time: 12:30-13:30
Room: Poster & Exhibition Area/Ground Level
Type: Poster Presentation
Malaria vector studies in the Republic of Korea: Vector parasite rates and habitat distribution
T. Klein 1 , H.-C. Kim 2 , L. M. Rueda 3 , D. H. Foley 3 , C. Li 3 , R. C. Wilkerson 3
1 65th Medical Brigade, Seoul, Korea, Republic of, 2 168th Multifunctional Medical Battalion, Seoul,
Korea, Republic of, 3 Walter Reed Army Institute of Research, Suitland, MD, USA
Background: In 1993, vivax malaria reemerged along the demilitarized zone (DMZ) of the
Republic of Korea (ROK) and rapidly increased to more than 4,000 cases by 2000. Although it
was presumed that malaria would rapidly spread throughout Korea, malaria transmission
remained concentrated near the DMZ. In 2005, two new species of Anopheles mosquitoes were
identified, with studies indicating that Anopheles pullus and An. kleini were likely the primary
vectors, while An. sinensis s.s., was a secondary vector. New evidence also suggests that An.
belenrae is a potential vector. Preliminary studies indicate that, although An. pullus, An. kleini,
and An. belenrae are found throughout Korea, population densities are highest near the DMZ and
possibly accounting for the high rates of transmission in this area.
Methods: More than 5,000 larvae were collected from selected habitats near Warrior Base
(approximately 3 Km south of the DMZ), labeled, placed in 100% ethanol, and shipped to the
Walter Reed Biosystematics Unit where they were identified by PCR to species. Additionally,
>7,000 adult anopheline mosquitoes were collected by light traps, Mosquito Magnets, and resting
collections at selected sites in northern Gyeonggi and Gangwon Provinces (1-30 Km south of the
DMZ). The head and thorax of individual specimens were identified to species by PCR and
sporozoites, and malaria infected mosquitoes identified by single step and semi-nested multiplex-
PCR.
Results: Larvae were identified to species from selected habitats and include Anopheles sinensis
s.s., An. pullus, An. kleini, An. belenrae, An. lesteri, and An. sineroides. Rice paddies were the
predominant habitat sampled. From adult collections, Plasmodium vivax was identified in An.
belenrae, An. kleini, An. pullus, and An. sinensis s.s. We discuss the potential role of these vector
species in maintaining malaria in the ROK.
Conclusion: The identification of potential malaria vectors, their role in malaria transmission, and
their distributions, including population density, are important in understanding the dynamics of
transmission and epidemiology of human cases in the ROK. Studies to determine the
distributions of Anopheles spp. and their relative population densities over their range are
needed.