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The majority of cases of undifferentiated acute febrile illness (AFI) in the tropics have an undefined etiology. In Thailand, AFI accounts for two-thirds of illnesses reported to the Ministry of Public Health. To characterize the bacterial and viral causes of these AFIs, we conducted molecular pathogen screening and serological analyses in patients who sought treatment in Chum Phae Hospital, Khon Kaen province, during the period from 2015 to 2016. Through integrated approaches, we successfully identified the etiology in 25.5% of cases, with dengue virus infection being the most common cause, noted in 17% of the study population, followed by scrub typhus in 3.8% and rickettsioses in 6.8%. Further investigations targeting viruses in patients revealed the presence of Guadeloupe mosquito virus (GMV) in four patients without other pathogen co-infections. The characterization of four complete genome sequences of GMV amplified from AFI patients showed a 93–97% nucleotide sequence identity with GMV previously reported in mosquitoes. Nucleotide substitutions resulted in amino acid differences between GMV amplified from AFI patients and mosquitoes, observed in 37 positions. However, these changes had undergone purifying selection pressure and potentially had a minimal impact on protein function. Our study suggests that the GMV strains identified in the AFI patients are relatively similar to those previously reported in mosquitoes, highlighting their potential role associated with febrile illness. [ABSTRACT FROM AUTHOR]

Although scrub typhus is one of the leading causes of acute febrile illnesses (AFI) in the Asia-Pacific region, with an estimated 1 million cases annually (1,2), its overall molecular epidemiology [...]

Scrub typhus is a febrile disease endemic to the Asia-Australia-Pacific region, where 1 million cases occur annually (1). The causative agent of scrub typhus in this region is the gram-negative [...]

To the Editor: Although rickettsioses caused by scrub typhus and typhus group rickettsiae are well recognized in Thailand, few spotted-fever group rickettsiae (SFGR), including Rickettsia honei TT118 and R. felis, [...]

The hepatitis E virus (HEV) is thought to be endemic throughout much of the world, particularly where sanitary infrastructure remains inadequate. HEV has been considered a military health threat and has been reported in several military environments. This study determined HEV seroconversion (defined by a 4-fold increase in antibody titers) occurring in Thai soldiers deployed to the HEV-endemic areas of East Timor, Afghanistan, and Iraq, as part of the U. N. multinational forces. With an average deployment of 6.4 months, the annualized seroconversion rates after deployments to East Timor, Afghanistan, Burundi, and Iraq were 1.9%, 4.6%, 4.6%, and 3.9%, respectively. [ABSTRACT FROM AUTHOR]

Scrub typhus caused by the Orientia tsutsugamushi. Rodents, particularly rats, serve as principal reservoir hosts. Infection in man is transmitted by the, chigger bite. Repellents provide an effective agent of protecting individuals from chigger. In the present study 6 plant essential oils were tested for evaluation of their repellent activity against the chigger, Leptotrombidium imphalum. The results showed that Clove oil was significantly more effective than others with ED50 and EC50 of 0.420 mg and 2.3%, followed by Zingiber oil (8.458 mg and 42.3%), Vetiver oil (19.582 mg and 97.9%), Turmeric oil (24.343 mg and 121.7%), Orange oil (27.310 mg and 136.6%) and Boesenbergia oil (30.486 mg and 152.4%). These results suggested that Clove oil was the most efficient repellent against chigger which is the vector for scrub typhus.

Scrub typhus is common among patients with acute fever in rural areas of Thailand. The authors prospectively recruited patients with acute fever from provincial Thai army hospitals. Dot-ELISA test for scrub typhus was done in hospitals and then compared with standard immunofluorescent assay for diagnosis of scrub typhus. Among 178 patients, scrub typhus was diagnosed by immunofluorescent assay in 10 patients (5.61%). The incidence was high in the northeastern and northern regions. Dot-ELISA gave positive results in 4 of 115 patients, while immunofluorescent assay gave positive results in 6 patients (sensitivity = 66.7%). No false positive results of Dot-ELISA were found among 109 patients (specificity = 100%). All patients gave negative results for murine typhus and Thai tick typhus using immunofluorescent assay. Regarding this present study, Dot-ELISA for scrub typhus has a good sensitivity and specificity and can be used in rural hospitals. This test could be useful for diagnosis of scrub typhus in hospitals where immunofluorescent assay is not available.