Rai J, Bandopadhyay D, 1978. Vertical transmission in chigger borne rickettsiosis. Indian J Med Res 68: 31–38.
Rapmund G, Dohany AL, Manikumaran C, Chan TC, Chan TC, 1972. Transovarial transmission of Rickettsia tsutsugamushi in Leptotrombidium (Leptotrombidium) arenicola Traub (Acarina: Trombiculidae). J Med Entomol 9: 71–72.
Rapmund G, Upham RW Jr, Kundin WD, Manikumaran C, Chan TC, 1969. Transovarial development of scrub typhus rickettsiae in a colony of vector mites. Trans R Soc Trop Med Hyg 63: 251–258.
Takahashi M, Murata M, Nogami S, Hori E, Kawamura A Jr, Tanaka H, 1988. Transovarial transmission of Rickettsia tsutsugamushi in Leptotrombidium pallidum successively reared in the laboratory. Jpn J Exp Med 58: 213–218.
Urakami H, Takahashi M, Hori E, Tamura A, 1994. An ultrastructural study of vertical transmission of Rickettsia tsutsugamushi during oogenesis and spermatogenesis in Leptotrombidium pallidum. Am J Trop Med Hyg 50: 219–228.
Takahashi M, Murata M, Misumi H, Hori E, Kawamura A Jr, Tanaka H, 1994. Failed vertical transmission of Rickettsia tsutsugamushi (Rickettsiales: Rickettsiaceae) acquired from rickettsemic mice by Leptotrombidium pallidum (Acari: trombiculidae). J Med Entomol 31: 212–216.
Walker JS, Chan CT, Manikumaran C, Elisberg BL, 1975. Attempts to infect and demonstrate transovarial transmission of R. tsutsugamushi in three species of Leptotrombidium mites. Ann N Y Acad Sci 266: 80–90.
Traub R, Wisseman CL Jr, Jones MR, O'Keefe JJ, 1975. The acquisition of Rickettsia tsutsugamushi by chiggers (trombiculid mites) during the feeding process. Ann N Y Acad Sci 266: 91–114.
Nakayama K, Yamashita A, Kurokawa K, Morimoto T, Ogawa M, Fukuhara M, Urakami H, Ohnishi M, Uchiyama I, Ogura Y, Ooka T, Oshima K, Tamura A, Hattori M, Hayashi T, 2008. The whole-genome sequencing of the obligate intracellular bacterium Orientia tsutsugamushi revealed massive gene amplification during reductive genome evolution. DNA Res 15: 185–199.
Rosenberg R, 1997. Drug-resistant scrub typhus: paradigm and paradox. Parasitol Today 13: 131–132.
Yamashita T, Kasuya S, Noda S, Nagano I, Ohtsuka S, Ohtomo H, 1988. Newly isolated strains of Rickettsia tsutsugamushi in Japan identified by using monoclonal antibodies to Karp, Gilliam, and Kato strains. J Clin Microbiol 26: 1859–1860.
Shirai A, Wisseman CL Jr, 1975. Serologic classification of scrub typhus isolates from Pakistan. Am J Trop Med Hyg 24: 145–153.
Qiang Y, Tamura A, Urakami H, Makisaka Y, Koyama S, Fukuhara M, Kadosaka T, 2003. Phylogenetic characterization of Orientia tsutsugamushi isolated in Taiwan according to the sequence homologies of 56-kDa type-specific antigen genes. Microbiol Immunol 47: 577–583.
Ohashi N, Koyama Y, Urakami H, Fukuhara M, Tamura A, Kawamori F, Yamamoto S, Kasuya S, Yoshimura K, 1996. Demonstration of antigenic and genotypic variation in Orientia tsutsugamushi which were isolated in Japan, and their classification into type and subtype. Microbiol Immunol 40: 627–638.
Ohashi N, Nashimoto H, Ikeda H, Tamura A, 1992. Diversity of immunodominant 56-kDa type-specific antigen (TSA) of Rickettsia tsutsugamushi. Sequence and comparative analyses of the genes encoding TSA homologues from four antigenic variants. J Biol Chem 267: 12728–12735.
Shirai A, Tanskul PL, Andre RG, Dohany AL, Huxsoll DL, 1981. Rickettsia tsutsugamushi strains found in chiggers collected in Thailand. Southeast Asian J Trop Med Public Health 12: 1–6.
Ruang-Areerate T, Jeamwattanalert P, Rodkvamtook W, Richards AL, Sunyakumthorn P, Gaywee J, 2011. Genotype diversity and distribution of Orientia tsutsugamushi causing scrub typhus in Thailand. J Clin Microbiol 49: 2584–2589.
Rodkvamtook W, Ruang-Areerate T, Gaywee J, Richards AL, Jeamwattanalert P, Bodhidatta D, Sangjun N, Prasartvit A, Jatisatienr A, Jatisatienr C, 2011. Isolation and characterization of Orientia tsutsugamushi from rodents captured following a scrub typhus outbreak at a military training base, Bothong district, Chonburi province, central Thailand. Am J Trop Med Hyg 84: 599–607.
Phasomkusolsil S, Tanskul P, Ratanatham S, Watcharapichat P, Phulsuksombati D, Frances SP, Lerdthusnee K, Linthicum KJ, 2009. Transstadial and transovarial transmission of Orientia tsutsugamushi in Leptotrombidium imphalum and Leptotrombidium chiangraiensis (Acari: Trombiculidae). J Med Entomol 46: 1442–1445.
Horinouchi H, Murai K, Okayama A, Nagatomo Y, Tachibana N, Tsubouchi H, 1996. Genotypic identification of Rickettsia tsutsugamushi by restriction fragment length polymorphism analysis of DNA amplified by the polymerase chain reaction. Am J Trop Med Hyg 54: 647–651.
Lerdthusnee K, Nigro J, Monkanna T, Leepitakrat W, Leepitakrat S, Insuan S, Charoensongsermkit W, Khlaimanee N, Akkagraisee W, Chayapum K, Jones JW, 2008. Surveys of rodent-borne disease in Thailand with a focus on scrub typhus assessment. Integr Zool 3: 267–273.
Jiang J, Chan TC, Temenak JJ, Dasch GA, Ching WM, Richards AL, 2004. Development of a quantitative real-time polymerase chain reaction assay specific for Orientia tsutsugamushi. Am J Trop Med Hyg 70: 351–356.
Thompson JD, Gibson TJ, Plewniak F, Jeanmougin F, Higgins DG, 1997. The CLUSTAL_X windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. Nucleic Acids Res 25: 4876–4882.
Tamura K, Peterson D, Peterson N, Stecher G, Nei M, Kumar S, 2011. MEGA5: molecular evolutionary genetics analysis using maximum likelihood, evolutionary distance, and maximum parsimony methods. Mol Biol Evol 28: 2731–2739.
Chao CC, Zhang Z, Wang H, Alkhalil A, Ching WM, 2008. Serological reactivity and biochemical characterization of methylated and unmethylated forms of a recombinant protein fragment derived from outer membrane protein B of Rickettsia typhi. Clin Vaccine Immunol 15: 684–690.
Sonthayanon P, Peacock SJ, Chierakul W, Wuthiekanun V, Blacksell SD, Holden MT, Bentley SD, Feil EJ, Day NP, 2010. High rates of homologous recombination in the mite endosymbiont and opportunistic human pathogen Orientia tsutsugamushi. PLoS Negl Trop Dis 4: e752.
Shirai A, Dohany AL, Ram S, Chiang GL, Huxsoll DL, 1981. Serological classification of Rickettsia tsutsugamushi organisms found in chiggers (Acarina: Trombiculidae) collected in Peninsular Malaysia. Trans R Soc Trop Med Hyg 75: 580–582.
Shirai A, Huxsoll DL, Dohany AL, Montrey RD, Werner RM, Gan E, 1982. Characterization of Rickettsia tsutsugamushi strains in two species of naturally infected, laboratory-reared chiggers. Am J Trop Med Hyg 31: 395–402.
Shirai A, Robinson DM, Brown GW, Gan E, Huxsoll DL, 1979. Antigenic analysis by direct immunofluorescence of 114 isolates of Rickettsia tsutsugamushi recovered from febrile patients in rural Malaysia. Jpn J Med Sci Biol 32: 337–344.
Tamura A, Yamamoto N, Koyama S, Makisaka Y, Takahashi M, Urabe K, Takaoka M, Nakazawa K, Urakami H, Fukuhara M, 2001. Epidemiological survey of Orientia tsutsugamushi distribution in field rodents in Saitama Prefecture, Japan, and discovery of a new type. Microbiol Immunol 45: 439–446.
Jiang J, Paris DH, Blacksell SD, Aukkanit N, Newton PN, Phetsouvanh R, Izzard L, Stenos J, Graves SR, Day NPJ, Richards AL, 2013. Diversity of the 47 kDa HtrA nucleic acid and translated amino acid sequences from 17 recent human isolates of Orientia. Vector Borne Zoonotic Dis 13: 367–375.
Chattopadhyay S, Richards AL, 2007. Scrub typhus vaccines: past history and recent developments. Hum Vaccin 3: 73–80.
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Characterization of the 56-kDa type-specific antigen (TSA) genes of Orientia tsutsugamushi (OT) from three naturally infected, laboratory-reared mite colonies comprising three species (Leptotrombidium deliense [Ld], Leptotrombidium imphalum [Li], and Leptotrombidium chiangraiensis [Lc]) has revealed the presence of single and coexisting OT genotypes found in individual chiggers. The Karp genotype was found in all of the chiggers examined, whereas Gilliam and UT302 genotypes were only observed in combination with the Karp genotype. From analysis of these OT genotypes after transmission from chiggers to mice it was determined that with the Lc and Li mites, the OT genotype composition in the rodent spleens post-infection had not changed and therefore resembled that observed in the feeding chiggers. However, only the Karp genotype was found in rodents after feeding by Ld chiggers carrying Karp and Gilliam genotypes. The current findings reveal a complex association among the host, pathogen, and vector.
Financial support: This work was supported by the Military Infectious Disease Research Program and the United States Army Medical Research and Materiel Command, Fort Detrick, MD.
Authors' addresses: Ratree Takhampunya, Bousaraporn Tippayachai, Sommai Promsathaporn, Surachai Leepitakrat, Taweesak Monkanna, and Anthony L. Schuster, Department of Entomology, AFRIMS, Bangkok, Thailand, E-mails: RatreeT@afrims.org, BousarapornT@afrims.org, SommaiP@afrims.org, SurachaiL@afrims.org, TaweesakM@afrims.org, and Schuster.Anthony@afrims.org. Melanie C. Melendrez, Viral Diseases Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, E-mail: email@example.com. Daniel H. Paris, Mahidol Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand, E-mail: firstname.lastname@example.org. Allen L. Richards, Rickettsial Diseases Research Program, Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD, E-mail: email@example.com. Jason H. Richardson, Entomology Branch, Walter Reed Army Institute of Research (WRAIR), Silver Spring, MD, E-mail: Jason.H.Richardson@us.army.mil.