Результаты поиска

Development of Recombinase Polymerase Amplification Assays for Detection of Orientia tsutsugamushi or Rickettsia typhi.

Sensitive, specific and rapid diagnostic tests for the detection of Orientia tsutsugamushi (O. tsutsugamushi) and Rickettsia typhi (R. typhi), the causative agents of scrub typhus and murine typhus, respectively, are necessary to accurately and promptly diagnose patients and ensure that they receive proper treatment. Recombinase polymerase amplification (RPA) assays using a lateral flow test (RPA-nfo) and real-time fluorescent detection (RPA-exo) were developed targeting the 47-kDa gene of O. tsutsugamushi or 17 kDa gene of R. typhi. The RPA assay was capable of detecting O. tsutsugamushi or R…

Phylogeographic diversity of Orientia tsutsugamushi strains from clinical isolates in South Korea.

Orientia tsutsugamushi, the causative agent of scrub typhus, is endemic to the Asia-Pacific region. In South Korea, the Boryong strain is considered dominant; however, nationwide phylogeographic distribution and genetic diversity based on clinical isolates remain incompletely characterized. In this study, 121 O. tsutsugamushi clinical isolates were collected from scrub typhus patients at 11 hospitals across South Korea between 2015 and 2024. Isolates were genotyped using 56-kDa gene sequencing and multilocus sequence typing (MLST) of seven housekeeping genes. Sequence analysis and phylogenetic…

A Compact Closed Genome of Orientia tsutsugamushi from Hainan Island, China Provides a TA763_A Reference and Reveals Repeat-Driven Remodeling.

Scrub typhus, caused by the obligate intracellular bacterium Orientia tsutsugamushi (O. tsutsugamushi), remains a major public-health concern in the Asia-Pacific region. Genome-wide inference is complicated by extensive repetitive DNA and frequent genome rearrangement. We isolated O. tsutsugamushi HMU_001 from a scrub typhus patient on Hainan Island, China. Intracellular morphology was examined and replication was quantified in endothelial cells. Using long-read sequencing with short-read polishing, we generated a closed circular genome and performed standardized comparative analyses across al…

Orientia tsutsugamushi and Epstein-Barr Virus coinfection presenting with transient fluctuating hearing loss: a case report.

Scrub typhus, caused by the obligate intracellular bacterium Orientia tsutsugamushi(O. tsutsugamushi), is an acute febrile illness. While neurological complications are known, hearing loss is an uncommon manifestation, and coinfection with Epstein-Barr virus(EBV) presents unique diagnostic and pathophysiological challenges. A 58-year-old woman presented with a 5-day history of high fever, severe headache, and constitutional symptoms. She reported transient, fluctuating bilateral hearing loss. Examination revealed characteristic eschars on her legs. Laboratory findings indicated hepatic impairm…

Small-molecule inhibition of the Orientia tsutsugamushi deubiquitylating enzyme OtDUB impairs bacterial reproduction.

Scrub typhus is a potentially fatal infectious disease caused by the obligate intracellular bacterium Orientia tsutsugamushi . While antibiotic treatment is generally effective, it requires extended treatment, and drug resistance and treatment failures have emerged. O. tsutsugamushi encodes a deubiquitylating enzyme, OtDUB, which interferes with host ubiquitin-dependent pathways. OtDUB cleaves ubiquitin from various substrates, but whether this activity can be selectively targeted by small molecules is unknown. Here we have screened a chemically diverse small-molecule library using a fluoresce…

Ориентия tsutsugamushi Modulates RIPK3 Cellular Systems, но не Inhibit Necroptosis.

Scrub tyhus — новая трансмиссивая болезнь, вызванная внутриклеточными бактериями Orientia tsutsugamushi. Некроптоз представляет собой одну из форм запрограммированной смерти клеток (ПХД) при посредничестве RIPK3 (серин/триониновый киназ-рецептор взаимодействует с белком 3) и его снизу эффектора MLKL (смешанный киназный домен). В то время как O. tsutsugamushi модифицирует апоптоз, еще одну форму PCD, его взаимодействие с некроптозом неизвестно. Значительная часть патобиологии Ориа связана с ее антыриновыми повторителями (АР), содержащими эффекты (Анкс). Два из них, Анк1 и Анк6, имеют сходство с

Совпадение в аннотации оригинала
Scrub typhus is an emerging chigger-borne disease caused by the obligate intracellular bacterium Orientia tsutsugamushi. Necroptosis is a form of programmed cell death (PCD) mediated by RIPK3 (serine/threonine kinase receptor interacting protein 3) and its downstream effector MLKL (mixed-lineage kinase domain-like). While O. tsutsugamushi modulates apoptosis…

Concurrent Infection with SARS-CoV-2 and Orientia tsutsugamushi during the COVID-19 Pandemic in the Maldives.

The COVID-19 pandemic was the worst public-health crisis in recent history. The impact of the pandemic in tropical regions was further complicated by other endemic tropical diseases, which can cause concurrent infections along with COVID-19. Here, we describe the clinical course of a patient with concurrent COVID-19 and scrub typhus infection. The patient's de-identified clinical data were retrieved retrospectively. The patient had progressive breathlessness at the time of presentation and was hospitalized for COVID-19. Respiratory examination revealed dyspnea, tachypnea, and coarse crepitatio…

Intranasal Immunization With Nanoparticles Containing an Orientia tsutsugamushi Protein Vaccine Candidate and a Polysorbitol Transporter Adjuvant Enhances Both Humoral and Cellular Immune Responses.

Scrub typhus, a mite-borne infectious disease, is caused by Orientia tsutsugamushi. Despite many attempts to develop a protective strategy, an effective preventive vaccine has not been developed. The identification of appropriate Ags that cover diverse antigenic strains and provide long-lasting immunity is a fundamental challenge in the development of a scrub typhus vaccine. We investigated whether this limitation could be overcome by harnessing the nanoparticle-forming polysorbitol transporter (PST) for an O. tsutsugamushi vaccine strategy. Two target proteins, 56-kDa type-specific Ag (TSA56)…

Infestation of Oriental House Rat (Rattus tanezumi) with Chigger Mites Varies along Environmental Gradients across Five Provincial Regions of Southwest China.

Chigger mites are the exclusive vector of scrub typhus. Based on field investigations of 91 survey sites in 5 provincial regions of Southwest China, this paper reported variations of chigger infestation on the oriental house rat (Rattus tanezumi) along various environmental gradients. A total of 149 chigger species were identified from 2919 R. tanezumi in the 5 provincial regions, and Leptotrombidium deliense (a major vector of scrub typhus in China) was the first dominant chigger species, followed by Ascoschoengastia indica and Walchia ewingi. Rattus tanezumi had a stable overall prevalence (…

A case of typhoidal tularemia in a male Japanese farmer.

In Japan, most tularemia cases occur after contact with hares (hunting, cooking) and involve the glandular or ulceroglandular form. Here, we present a case of typhoidal tularemia in a 72-year-old Japanese male farmer who presented with fever, fatigue, and right lower abdominal pain. Computed tomography revealed intestinal wall thickening at the ascending colon, pleural effusion, and ascites. Following an initial diagnosis of bacterial enteric infection, his symptoms deteriorated after a week-long cephalosporin treatment course. The patient lived in an area endemic for scrub typhus; the antibio…

Flinders Island spotted fever rickettsioses caused by "marmionii" strain of Rickettsia honei, Eastern Australia.

Australia has 4 rickettsial diseases: murine typhus, Queensland tick typhus, Flinders Island spotted fever, and scrub typhus. We describe 7 cases of a rickettsiosis with an acute onset and symptoms of fever (100%), headache (71%), arthralgia (43%), myalgia (43%), cough (43%), maculopapular/petechial rash (43%), nausea (29%), pharyngitis (29%), lymphadenopathy (29%), and eschar (29%). Cases were most prevalent in autumn and from eastern Australia, including Queensland, Tasmania, and South Australia. One patient had a history of tick bite (Haemaphysalis novaeguineae). An isolate shared 99.2%, 99…

Acute renal failure due to acute tubular necrosis caused by direct invasion of Orientia tsutsugamushi.

We describe a scrub typhus patient with acute renal failure for whom a diagnosis was made based on serology as well as immunohistochemical (IHC) staining and an electron microscopic examination (EM) of a renal biopsy specimen. For our case, we demonstrated by IHC staining and EM that renal failure was caused by acute tubular necrosis due to a direct invasion of Orientia tsutsugamushi.

Evidence of infection with Leptospira interrogans and spotted fever group rickettsiae among rodents in an urban area of Osaka City, Japan.

We examined 33 rodents captured in an urban area of Osaka City, Japan for IgG antibodies against Seoul virus, severe fever with thrombocytopenia syndrome virus, hepatitis E virus, Leptospira interrogans, Yersinia pestis, spotted fever, typhus and scrub typhus group rickettsiae. We found that 3 (9.1%) and 1 (3.0%) of the 33 rodents had antibodies against L. interrogans and spotted fever group rickettsiae, respectively. DNAs of leptospires were detected from 2 of the 3 seropositive rodents, but DNA of rickettsia was not detected. Phylogenetic analysis and multiple locus sequence typing revealed …