Dual exposure of Rickettsia typhi and Orientia tsutsugamushi in the field-collected Rattus rodents from Thailand.

Field-collected rodents and fleas from ten provinces covering four regions of Thailand were investigated for possible rickettsial pathogen infections. The 257 trapped-rodents belonged to 12 species. Five species of Genus Rattus accounted for 93% of the total capture, of which Rattus exulans and Rattus norvegicus were the two major species caught.

Influence of Orientia tsutsugamushi infection on the developmental biology of Leptotrombidium imphalum and Leptotrombidium chiangraiensis (Acari: Trombiculidae).

Leptotrombidium chiangraiensis Tanskul & Linthicum, and Leptotrombidium imphalum Vercammen-Grandjean are important vectors of scrub typhus in rice field habitats in northern Thailand. The developmental biology of all stages of the life cycle of two generations of these species of mites infected with Orientia tsutsugamushi (Hayashi) and uninfected mites is reported. The development of the infected lines of both F1 and F2 L.

Seasonal abundance and distribution of Anopheles larvae in a riparian malaria endemic area of western Thailand.

Three taxonomic groups of Anopheles larvae were morphologically identified within the Funestus Group (Minimus Subgroup and Aconitus Subgroup) (75.63%), Maculatus Group (20.47%), and Barbirostris Group (0.

Irritant and repellent responses of Anopheles harrisoni and Anopheles minimus upon exposure to bifenthrin or deltamethrin using an excito-repellency system and a live host.

Feeding responses of Anopheles harrisoni and An. minimus were evaluated following exposure to 2 pyrethroid insecticides, bifenthrin or deltamethrin, using an excito-repellency test system in the presence and absence of live host cues. The results demonstrated that contact irritancy was the primary action of bifenthrin or deltamethrin in both mosquito species.

Rift Valley fever virus-infected mosquito ova and associated pathology: possible implications for endemic maintenance.

Background: Endemic/Enzootic maintenance mechanisms like vertical transmission (pathogen passage from infected adults to their offspring) are central in the epidemiology of zoonotic pathogens. In Kenya, Rift Valley fever virus (RVFV) may be maintained by vertical transmission in ground-pool mosquitoes such as . RVFV can cause serious morbidity and mortality in humans and livestock.