Executive Summary Ticks and mites (subphylum Chelicerata: class Acari) transmit a greater variety of human and animal pathogens than any other arthropod vector. Tickand mite-borne diseases are global health problems caused by a variety of bacterial, viral and protozoan pathogens, which are responsible for significant morbidity and thousands of human deaths annually. The incidence of many tick-b...

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 ...

Thirteen different laboratory colonies of Leptotrombidim chiggers [L. chiangraiensis Tanskul & Linthicum, L. deliense Walch and L. imphalum (Vercammen-Grandjean &Langston)] were evaluated for their ability to transmit Orientia tsutsugamushi (Hyashi) to mice. Of 4,372 transmission attempts using individual chiggers from all 13 colonies, 75% (n = 3,275) successfully infected mice. Transmission ra...

Ectoparasitic arthropods are often vectors of rickettsiosis. We conducted a survey of ectoparasites on U.S. military facilities throughout Japan with the use of specimens submitted by pest control, public health, and veterinary personnel. Over 1,600 individual ectoparasites were collected. Fifteen species were identified, including several significant vectors of human diseases such as scrub typ...

A total of 9,281 larval chigger mites were collected from small mammals captured at Hwaseong-gun, Gyeonggi-do (Province) (2,754 mites from 30 small mammals), Asan city, Chungcheongnam-do (3,358 mites from 48 mammals), and Jangseong-gun, Jeollanam-do (3,169 for 62 mammals) from April-November 2009 in the Republic of Korea (= Korea) and were identified to species. Leptotrombidium pallidum was the...

In recent years, the incidence of tsutsugamushi disease has increased in Nan Peng Lie Islands in China, and the disease has not been recorded in this region. The natural foci of tsutsugamushi disease were investigated in this paper. Isolation of Orientia tsutsugamushi and the study of preventive measures were also performed. The region was the island natural foci of south subtropical zone. The ...

To clarify the geographical distribution of scrub typhus vectors in Korea, a survey of larval trombiculid mites was conducted from 2005 to 2007 by collecting wild small mammals twice a year (spring and autumn) at 24 sites nationwide. A total of 67,325 mites representing 4 genera and 14 species were collected from 783 trapped rodents, corresponding to a chigger index (number of chigger mites per...

The morphology and cuticular ultrastructure of the quiescent instars prelarva, proto-and tritonymph of the trombiculid mites, Hirsutiella zachvatkini, Leptotrombidium orientale and Leptotrombidium schlugerae (Trombiculidae) were investigated with transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Their post-embryonic life cycle is considered in terms of their moultin...

Intersection results for families of H-convex sets in H-spaces are given. These extend known results concerning families of convex sets in topological vector spaces, such as the Berge-Klee intersection theorem and a previous result of the author. MSC 2000. 52A01, 14E20.

Transovarial transmission of Orientia tsutsugamushi in colonies of Leptotrombidium palpale was studied in the parent and F1 and F2 generations. Both transovarial transmission and filial infection rates were 100% in the parent and F1 generations of Leptotrombidium palpale. The filial infection rate in the F1 generation was 100%, but it declined to 94.3% in the F2 progeny. The sex ratio of the F1...