Efficiency of Leptotrombidium Chiggers (Acari: Trombiculidae) at Transmitting Orientia tsutsugamushi to Laboratory Mice

• Published in: Journal of medical entomology Vol. 39; no. 3; pp. 521 - 525
• Main Authors: Lerdthusnee, Kriangkrai, Khlaimanee, Nittaya, Monkanna, Taweesak, Sangjun, Noppadon, Mungviriya, Siriporn, Linthicum, Kenneth J., Frances, Stephen P., Kollars Jr, Thomas M., Coleman, Russell E.
• Format: Journal Article
• Language: English
• Published: Lanham, MD Entomological Society of America 01-05-2002; Oxford University Press
• Subjects: Analysis; Animals; Arachnid Vectors - microbiology; Biological and medical sciences; chiggers; Disease Models, Animal; Fundamental and applied biological sciences. Psychology; Health aspects; House mouse; Leptotrombidium chiangraiensis; Leptotrombidium deliense; Leptotrombidium imphalum; Medically important nuisances and vectors, pests of stored products and materials: population survey and control; Mice; Orientia tsutsugamushi; Scrub Typhus - microbiology; Scrub Typhus - transmission; transmission; Trombiculidae - microbiology; Vectors. Intermediate hosts; Host parasite relation; Acari; Rickettsial infection; Transmission from animal to animal; Infectivity; Bacteria; Laboratory animal; Vector; Rickettsialosis; Interspecific comparison; Rodentia; Host; Infection; Rickettsiales; Acariformes; Arachnida; Vertebrata; Mammalia; Rickettsia tsutsugamushi; Mouse; Actinedida; Arthropoda; Bacteriosis; Rickettsieae; Invertebrata; Rickettsiaceae; Trombiculidae
• ISSN: 0022-2585; 1938-2928
• DOI: 10.1603/0022-2585-39.3.521

Thirteen different laboratory colonies of Leptotrombidium 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 rates for the individual chigger colonies ranged from 7 to 80%. Increasing the number of chiggers that fed on a given mouse generally increased transmission rates. Transmission of O. tsutsugamushi to mice by different generations (F1–F11) of certain chigger colonies was stable; however, transmission rates varied greatly in other colonies. Transmission rates (both vertical and horizontal) of several L. chiangraiensis colonies and the L. deliense colony were the highest, suggesting that these colonies may be useful for the development of a chigger-challenge model that can be used to evaluate the efficacy of candidate scrub typhus vaccines or therapeutic agents in laboratory mice.