A survey to determine the geographical distribution and relative abundance of potential vectors of scrub typhus was conducted from October to November 2006 at 13 localities throughout the Republic of Korea. Apodemus agrarius accounted for 97.6% (80/82) of all rodents, while only 2 Myodes regulus (2/82) were collected. A total of 10,860 chiggers were collected from A. agrarius belonging to 4 genera and 8 species, while only Walchia fragilis (40) was collected from Myodes regulus. Leptotrombidium pallidum (8,137; 74.9%), a vector of scrub typhus, was the predominant species collected from A. agrarius followed by Leptotrombidium scutellare (2,057, 18.9%), Leptotrombidium palpale (279; 2.7%), Leptotrombidium orientale (232; 2.1%), and Leptotrombidium zetum (79; 0.7%), Neotrombicula tamiyai (58; 0.5%), Euschoengastica koreaensis (16; 0.1%), and Cheladonta ikaoensis (2; < 0.1%). L. pallidum was the predominant chigger collected at collection sites in Gangwon (100%), Gyeonggi (87.2%), Chungnam (100%), Chungbuk (100%), Jeonbuk (73.9%), Jeonnam (77.0%), and Gyeongbuk (66.1%) provinces, whereas L. scutellare was the predominant chigger collected in Gyeongnam province (77.9%) and Jeju Island (62.3%). Data suggest a correlation between chigger population abundance and human cases of scrub typhus in Korea.
Animals ; Arvicolinae/*parasitology ; *Disease Vectors ; Geography ; Mites/*microbiology ; Murinae/*parasitology ; Orientia tsutsugamushi/*isolation & purification ; Republic of Korea ; Scrub Typhus/transmission

No abstract available.
Animal ; Antibodies, Bacterial/blood ; Antigens, Bacterial/blood ; Human ; Mites/microbiology ; Orientia tsutsugamushi/classification/immunology ; Scrub Typhus/diagnosis/*epidemiology/immunology

We investigated the prevalence of Bartonella infections in ticks, mites and small mammals (rodents, insectivores and weasels) collected during 2001 through 2004, from various military installations and training sites in Korea, using PCR and sequence analysis of 16S rRNA, 23S rRNA and groEL heat shock protein genes. The prevalence of Bartonella spp. was 5.2% (n = 1, 305 sample pools) in ticks, 19.1% (n = 21) in mesostigmatid mites and 13.7% (n = 424 individuals) in small mammals. The prevalence within the family Ixodidae was, 4.4% (n = 1, 173) in Haemaphysalis longicornis (scrub tick), 2.7% (n = 74) in H. flava, 5.0% (n = 20) in Ixodes nipponensis, 11.1% (n = 9) in I. turdus, 33.3% (n = 3) in I. persulcatus and 42.3% (n = 26) in Ixodes spp. ticks. In rodents, the prevalence rate was, 6.7% (n = 373) in Apodemus agrarius (striped field mouse) and 11.1% (n = 9) in Eothenomys regulus (Korean red-backed vole) and in an insectivore, Crocidura lasiura, 12.1% (n = 33). Neither of the two weasels were positive for Bartonella spp. Phylogenetic analysis based on amino acid sequence of a portion of the groEL gene amplified from one A. agrarius spleen was identical to B. elizabethae species. We demonstrated the presence of Bartonella DNA in H. longicornis, H. flava and I. nipponensis ticks, indicating that these ticks should be added to the growing list of potential tick vectors and warrants further detailed investigations to disclose their possible roles in Bartonella infection cycles.
Animals ; Bartonella/classification/*isolation&purification ; DNA, Bacterial/isolation&purification ; Disease Vectors ; GroEL Protein/genetics ; Mammals/*microbiology ; Mites/*microbiology ; Polymerase Chain Reaction ; RNA, Ribosomal, 16S/genetics ; RNA, Ribosomal, 23S/genetics ; Ticks/*microbiology

OBJECTIVETo investigate whether HV and Ot can coexist in their host (Leptotrombidium scutellare).

METHODSCollecting the separate Leptotrombidium scutellare and the ones from mice in epidemic area. The cells of mites at larva, nymph, and adult stages were cultured and made into smear. In situ RT-PCR and PCR were used to detect and locate HV RNA and Ot DNA in the primary cultured cells.

RESULTSPositive signals of HV RNA and Ot DNA distributed mostly in epithelial cells of digestive system and ovary cells of larva and nymph. The positive rate increased by the generation of passages.

CONCLUSIONCoinfection of HV and Ot did exist in wild Leptotrombidium scutellare.

Animals ; Cells, Cultured ; DNA, Bacterial ; analysis ; Female ; Hantavirus ; isolation & purification ; Mice ; Mites ; microbiology ; virology ; Orientia tsutsugamushi ; isolation & purification ; RNA, Viral ; analysis ; Reverse Transcriptase Polymerase Chain Reaction