Siriporn PhasomkusolsilPanita TanskulSupaporn RatanathamPochaman WatcharapichatDuangporn PhulsuksombatiStephen P. FrancesKriangkrai LerdthusneeKenneth J. LinthicumArmed Forces Research Institute of Medical Sciences, ThailandMahidol UniversityAustralian Army Malaria InstituteUSDA Agricultural Research Service, Gainesville2018-09-132018-09-132009-11-01Journal of Medical Entomology. Vol.46, No.6 (2009), 1442-1445002225852-s2.0-75549090559https://repository.li.mahidol.ac.th/handle/20.500.14594/26967Transovarial transmission of Orientia tsutsugamushi (Hayashi) in laboratory colonies of Leptotrombidium chiangraiensis Tanskul & Linthicum and Leptotrombidium imphalum (Vercammen-Grandjean & Langston) (Acari: Trombiculidae) was studied for two generations. In L. chiangraiensis, the transovarial and filial infection rate was 100% in each generation. Only infected females were produced. In L. imphalum, the transovarial infection rate of the parental generation was 100% but declined to 93.3% in the F 1 generation. The overall filial infection rate was 100% in the F1 but was only 62.3% in the F 2 generation. In infected lines, only infected females were produced in the F 1 generation, but 1.5% of the F 2 progeny were infected males. Lower rates of transovarial transmission in L. imphalum may be the cause of the lower natural infection rates found in nature.Mahidol UniversityAgricultural and Biological SciencesImmunology and MicrobiologyMedicineVeterinaryArticleSCOPUS10.1603/033.046.0628