Comparative epidemiological studies on vector/reservoir animals of tsutsugamushi disease between high and low endemic areas in Korea

, Ree, H I; , Cho, M K; , Lee, I Y; , Jeon, S H

doi:1995.33.1.27

Korean J Parasito > Volume 33(1):1995 > Article

Original Article


Korean J Parasitol. 1995 Mar;33(1):27-36. English. Published online Mar 20, 1995. http://dx.doi.org/10.3347/kjp.1995.33.1.27
Copyright © 1995 by The Korean Society for Parasitology


Comparative epidemiological studies on vector/reservoir animals of tsutsugamushi disease between high and low endemic areas in Korea
Han-Il Ree,^*¹Min-Kee Cho,²In-Yong Lee,¹ and Soung-Hoo Jeon¹
¹Institute of Tropical Medicine, Yonsei University, Seoul 120-752, Korea.
²Department of Microbiology, College of Medicine, Hallym University, Chunchon 200-702, Korea.

Received December 01, 1994; Accepted January 04, 1995.
Abstract
Comparative epidemiological studies on vector reservoir animals of tsutsugamushi disease were carried out in between south coast (the highest endemic) areas and east coast (low endemic) areas in October 1993. Fauna of field rodents and their population densities were not different between two areas. Antibody positive rate of Apodemus agrarius sera was higher in east coast (43.2% in south coast and 63.6% in east coast). High correlation (r = 0.87) was shown between antibody positive rate of A. agrarius sera and population density of the vector mites (Leptotrombidium scutellare and L. pallidum). L. scutellare was predominant in south coast, showing 110.6 chigger index (74.9% of the total chiggers), whereas L. pallidum was predominant in east coast, showing 126.3 chigger index (60.4% of the total). As higher population density of L. scutellare was found in south coast where the prevalence rate of tsutsugamushi disease is the highest, it is believed that L. scutellare is more important vector species than L. pallidum, which may result from more frequent vector-human contact.

Figures


	Fig. 1 Study sites along south and east coast of the Korean Peninsula.


	Fig. 2 Correlation between chigger indices of the vectors and antibody positive rate of Apodemus agrarius sera in October 1993

Tables


	Table 1 Field rodent collections by using 98 Sherman traps at each study area in October 1993


	Table 2 Chigger index of each species of the field rodents for assessing host preferences of chigger mites


	Table 3 Species and total numbers of the chigger mites collected in study areas


	Table 4 Comparative density of chigger mites (chigger index) on Apodemus agrarius


	Table 5 Antibody positive rate of Apodemus agrarius sera against R. tsutsugamushi in October 1993


	Table 6 Prevalence rate of tsutsugamushi disease by province in Korea in 1991 and 1992


	Table 7 Prevalence rate of tsutsugamushi disease along east and south coastal areas of Korea in 1991 and 1992

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