Geographical distribution of vectors and sero-strains of tsutsugamushi disease at mid-south inland of Korea

, Ree, H I; , Lee, I Y; , Jeon, S H; , Yoshida, Y

doi:1997.35.3.171

Korean J Parasito > Volume 35(3):1997 > Article

Original Article


Korean J Parasitol. 1997 Sep;35(3):171-179. English. Published online Feb 11, 2009. http://dx.doi.org/10.3347/kjp.1997.35.3.171
Copyright © 1997 by The Korean Society for Parasitology


Geographical distribution of vectors and sero-strains of tsutsugamushi disease at mid-south inland of Korea
H I Ree,^*¹I Y Lee,¹S H Jeon,¹ and Y Yoshida²
¹Department of Parasitology, College of Medicine, Yonsei University, Seoul 120-752, Korea.

Received August 18, 1997; Accepted September 01, 1997.
Abstract
Studies of geographical distributions and relative population densities of the vector mites of tsutsugamushi disease were carried out in October 1996 at 12 locations of the mid-south inland of the Korean peninsula, where chigger mites have been never studied. Of 177 field rodents and insectivores collected, 154 (87.0%) were Apodemus agrarius. Total 25,707 chigger mites were collected and 14 species were identified, of which Leptotrombidium pallidum was predominant (79.8%) and L. palpale the next (8.9%). L. pallidum, the vector species, was widely distributed in all study areas, showing the highest density at Cho-o 2-dong, Sangju-si (chigger index 201.8), and the lowest at Tanwol-dong. Chungju-si (chigger index 40.7). The other vector species, L. scutellare was found only at the southern part of the study area such as Yobae and Mipyong, Kumrung-gun and Unsu, Kimchon-si. The northernmost areas of the L. scutellare distribution were coincided with the areas where anual mean air temperature is above 10.0 C. Among 157 A. agrarius sera tested, 48.3% was Karp, 1.7% Gilliam and 3.3% Kuroki. The rest of the sera were not able to determine the sero-type because of the cross antigen-antibody reactions among the tested sero-types.

Figures


	Fig. 1 Geographical distribution and population densities of L. pallidum in Korea. The figures are chigger indices of L. pallidum.


	Fig. 2 Geographical distribution and population densities of L. pallidum in Korea. The figures are chigger indices of L. scutellare. The dot line is the northernmost distribution of L. scutellare.


	Fig. 3 Thirty years annual mean air temperature of each meteorological station in Korea. The dot line is the northernmost area where the mean air temperature is above 10.0℃.

Tables


	Table 1 Field rodent and insectivore collections at 11 locations of the inland of Korea in October 1996


	Table 2 Number and species of the chigger mites collected in the inland of Korea in October 1996


	Table 3 Chigger-infestation rates and chigger indices of field rodents and insectivores collected at the 12 study locations in October 1996


	Table 4 Geographical distribution and population density of trombiculid mites infested on Apodemus agrarius in the inland of Korea in October 1996


	Table 5 Antibody positive rate of A. agrarius sera against O. tsutsugamushi serotypes, using IFA test

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