title: Monthly occurrence of vectors and reservoir rodents of scrub typhus in an endemic area of Jeollanam-do, Korea.
abstract: Monthly surveys were conducted to investigate the occurrence of chigger mites and seroprevalence of scrub typhus among small mammals in Jeollanam-do, the southwestern part of Korea, from November 2006 through October 2007. Fifty-eight small mammals, including 57 Apodemus agrarius (98.3%) and 1 Crocidura lasiura (1.7%), were captured, and a total of 4,675 chigger mites representing 4 genera and 8 species were collected from them. The chigger infestation rate among small mammals was 69.0%. The most predominant species in A. agrarius was Leptotrombidium scutellare (54.0%), followed by Leptotrombidium pallidum (39.4%), Leptotrombidium orientale (4.4%), Leptotrombidium palpale (1.1%), Neotrombicula tamiyai (0.6%), Eushoengastia koreaensis (0.3%), Neotrombicula gardellai (0.3%), and Cheladonta ikaoensis (<0.1%). The chigger index of A. agrarius was the highest in October (740.0), followed by November (242.0), September (134.6), March (98.3), February (38.2), January (35.3), December (34.5), April (30.8), and May (1.7). The average antibody positive rate of scrub typhus in wild rodents was 50.0%. The seropositive rates were high in October (100.0%) and November (83.3%), whereas those in other months were relatively low (28.6-57.1%). The chigger index of L. scutellare rapidly increased in September to form an acuminate peak in October, followed by a gradual decline. These results suggest that the outbreak of scrub typhus in the southwestern part of Korean peninsula is mostly due to L. scutellare.
authors.affiliation: Department of Microbiology, Konkuk University School of Medicine, Chungju 380-701, Korea.
authors.forename: Seung Hyun
authors.initials: SH
authors.lastname: Lee
authors.forename: Young-Sun
authors.initials: YS
authors.lastname: Lee
authors.forename: In Yong
authors.initials: IY
authors.lastname: Lee
authors.forename: Jae Won
authors.initials: JW
authors.lastname: Lim
authors.forename: Hee-Kwan
authors.initials: HK
authors.lastname: Shin
authors.forename: Jae-Ran
authors.initials: JR
authors.lastname: Yu
authors.forename: Seobo
authors.initials: S
authors.lastname: Sim
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000918:Antibody Specificity; D001096:Arachnid Vectors / Q000382:microbiology*; D004197:Disease Reservoirs; D006801:Humans; D051189:Murinae / Q000469:parasitology; D012285:Orientia tsutsugamushi / Q000276:immunology*; D011157:Population Dynamics; D062486:Public Health Surveillance; D056910:Republic of Korea / Q000453:epidemiology; D012376:Rodent Diseases / Q000469:parasitology / Q000635:transmission; D012612:Scrub Typhus / Q000453:epidemiology / Q000635:transmission*; D012621:Seasons; D016036:Seroepidemiologic Studies; D012788:Shrews / Q000469:parasitology; D013045:Species Specificity; D014323:Trombiculiasis / Q000469:parasitology / Q000662:veterinary; D014324:Trombiculidae / Q000382:microbiology*
chemical_list: D000907:Antibodies, Bacterial