Distribution of Trombiculid Mites Collected from Wild Rodents in a Certain Area of Kyung-Ki Province

다국어 초록 (Multilingual Abstract)

The purpose of this study is to investigate the distribution of the trombiculid mites, especially Leptotrombidium pallidum which is considered to be the most probable lector species of tsutsugamushi disease in Korea.
Mites were collected from the wild rodents captured with Sherman traps in a certain area of Pyung-Taik Gun, Kyung-Hi Province from October 1989 to November 1990.
The results were summarized as follows:
1. A total of 2, 419 trombiculid larvae belonging to 4 species of 3 genera was collected from 77 wild rodents of 69 Apodemus agrarius and 8 Crocidura species.
2. The species of trombiculid mites were L. Pallidum (96.4%), Neotrombicula Japonica (3.1%), L. Palpale (0.3%), Cheladonta ikaoensis (0.1%).
3. The average number of collected trombiculid mites per one wild rodent was 34.0 in A. agrarius and 9.4 in Crocidura species.
4. The total number of trombiculid mites collected from 10 wild rodents that were alive during the 5 consecutive collection days was 785, and 16.7% of the mites was collected in the first day, 44.2% in the second day, 21.7% in the third day, 17.1% in the fourth day and 0.4% in fifth day. The total number of trombiculid mites collected from the 4 wild rodents that were dead within the first day of collection was 71, and 93.0% of the mites was collected in the second day.
5. Most of the L. pallidum was collected in March, May, October and November and none in June, July and August. The numbers of L. pallidum per one wild rodent were 139.6 in October 1989, 125.5 in March 1990, 41 3 in October 1990, 33.1 in November 1990 and 30.5 in April 1990 in decreasing orders.
From these results, A. agrarius was the main wild rodent from which L. pallidum was collected and the seasonal distribution of L. pallidum was partly correlated with the known seasonal distribution of tsutsugamushi disease in Korea.