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The exposure of a research team to chigger mites in southern Chile allowed the first identification of a trombiculid species as vector and reservoir of scrub typhus outside the tsutsugamushi triangle, providing unique insights into the ecology and transmission of this recently discovered rickettsial infection in South America. [ABSTRACT FROM AUTHOR]

Scrub typhus, a neglected infectious disease caused by the obligate intracellular bacterium Orientia tsutsugamushi , is a major cause of fever across the Asia Pacific region with more than a billion people at risk. Treatment with antibiotics such as doxycycline or chloramphenicol is effective for the majority of patients. In the 1990s, reports from northern Thailand raised a troubling observation; some scrub typhus patients responded poorly to doxycycline, which investigators attributed to doxycycline resistance. Despite the controversial nature of these reports, independent verification was neglected, with subsequent studies speculating on the role of doxycycline resistance in contributing to failure of treatment or prophylaxis. In this review, we have outlined the evidence for drug-resistant Orientia tsutsugamushi , assessed the evidence for doxycycline resistance, and highlight more recent findings unsupportive of doxycycline resistance. We conclude that doxycycline resistance is a misconception, with treatment outcome likely to be determined by other bacterial, host, and pharmacological factors. [ABSTRACT FROM AUTHOR]

Background Substantial outbreaks of scrub typhus, coupled with the discovery of this vector-borne disease in new areas, suggest that the disease remains remarkably neglected. The objectives of this study were to map the contemporary and potential transmission risk zones of the disease and to provide novel insights into the health burden imposed by scrub typhus in southern China. Methods Based on the assembled data sets of annual scrub typhus cases and maps of environmental and socioeconomic correlates, a boosted regression tree modeling procedure was used to identify the environmental niche of scrub typhus and to predict the potential infection zones of the disease. Additionally, we estimated the population living in the potential scrub typhus infection areas in southern China. Results Spatiotemporal patterns of the annual scrub typhus cases in southern China between 2007 and 2017 reveal a tremendous, wide spread of scrub typhus. Temperature, relative humidity, elevation, and the normalized difference vegetation index are the main factors that influence the spread of scrub typhus. In southern China, the predicted highest transmission risk areas of scrub typhus are mainly concentrated in several regions, such as Yunnan, Guangxi, Guangdong, Hainan, and Fujian. We estimated that 162 684 million people inhabit the potential infection risk zones in southern China. Conclusions Our results provide a better understanding of the environmental and socioeconomic factors driving scrub typhus spread, and estimate the potential infection risk zones beyond the disease's current, limited geographical extent, which enhances our capacity to target biosurveillance and help public health authorities develop disease control strategies. [ABSTRACT FROM AUTHOR]

We developed a scoring system to differentiate severe fever with thrombocytopenia syndrome (SFTS) in 21 patients with SFTS and 91 with scrub typhus; it provided 100% sensitivity and 97% specificity (score > 1). Criteria included altered mental status, leukopenia, prolonged activated partial thromboplastin time, and normal C-reactive protein (1-point each). [ABSTRACT FROM AUTHOR]

Murine typhus, an acute febrile illness caused by Rickettsia typhi, is distributed worldwide. Mainly transmitted by the fleas of rodents, it is associated with cities and ports where urban rats (Rattus rattus and Rattus norvegicus) are abundant. In the United States, cases are concentrated in suburban areas of Texas and California. Contrary to the classic rat-flea-rat cycle, the most important reservoirs of infection in these areas are opossums and cats. The cat flea, Ctenocephalides fells, has been identified as the principal vector. In Texas, murine typhus cases occur in spring and summer, whereas, in California, cases have been documented in summer and fall. Most patients present with fever, and many have rash and headache. Serologic testing with the indirect immunofluorescence assay is the preferred diagnostic method. Doxycycline is the antibiotic of choice and has been shown to shorten the course of illness. [ABSTRACT FROM AUTHOR]

Presents a case study on epidemic typhus meningitis in New Mexico. Background on the case; Methods and results; Discussion.

Dr. Theodore E. Woodward was one of the early giants of infectious diseases research who set the groundwork for the field. He was the first to evaluate vaccines against typhus, employing volunteers to test the effectiveness of the vaccines. This led to the evaluation of chloramphenicol for the treatment of rickettsial diseases and typhoid fever. Subsequently, he was influential in establishing a unique volunteer unit in Maryland in which a wide range of vaccines were evaluated. [ABSTRACT FROM AUTHOR]

Examines the prevalence of epidemic typhus, trench fever and relapsing fever due to louse-transmitted bacterial infections among the rural Andean communities in Peru. Binomial analysis of sex-stratified data relating to the prevalence of louse infection among the people from four Andean villages in Peru; Clinical, epidemiological and laboratory data of volunteers in Peru; Correlation between altitude and ectoparasitic infestation among the villages.

The article offers information on various research related to clinical infectious disease (CID). A study by L. P. Morse and colleagues examined a prospective database of all culture-confirmed episodes of melioidosis in the Northern Territory of Australia during the period 1989-2008. On the other, M. Henry and colleagues examined the feasibility of examination of stool in the diagnosis of pulmonary tuberculosis. In the third study, researchers A. S. Chapman and colleagues presented the findings of their study in their paper "Cluster of sylvatic epidemic typhus cases associated with flying squirrels."