L J Ting, X L Tan, V Tiong, S Abubakar, I Abdullah, S A Karsani, K-G Chan, K-O Chua, H-S Yong, Y J M Liew
{"title":"Sustained antibody response to a linear epitope of Nipah virus fusion protein in human survivor serum samples.","authors":"L J Ting, X L Tan, V Tiong, S Abubakar, I Abdullah, S A Karsani, K-G Chan, K-O Chua, H-S Yong, Y J M Liew","doi":"10.47665/tb.43.1.002","DOIUrl":"10.47665/tb.43.1.002","url":null,"abstract":"<p><p>Nipah virus (NiV), a pathogen with pandemic potential, lacks approved treatments or vaccines, highlighting the urgent need for research on immune-targeted antigenic determinants. A significant gap persists in NiV research, as studies on the fusion (F) protein critical for viral entry as well as the B cells epitopes, have primarily focused on computational prediction rather than experimental validation of immunogenic epitopes obtained through immunoinformatics approach. This study focused on the conserved F protein across NiV human isolates and employed an immunoinformatics approach to predict linear B-cell epitopes capable of direct immune activation. Predicted epitopes were screened for antigenicity, toxicity, and allergenicity. Molecular docking analysis was performed to evaluate its binding affinity with B-cell receptors (BCRs). To validate its immunogenicity, the LF6 peptide was synthesized and used in an indirect ELISA to test sera from cohort previously infected with NiV as well as with negative cohort. Epitope LF6 (LISNIEIGFCL) was identified as a strong candidate based on its immunogenic properties. Molecular docking showed favorable binding of LF6 with BCR. ELISA results revealed that one sera from the survival cohort showed positive response which is an IgG antibody response 2-fold higher (0.343) than the cut-off value (0.0171). This study provides the first reported evidence linking computational predictions with functional immune reactivity for a B-cell epitope of NiV. The findings suggest that LF6 has the potential to elicit specific immune responses. However, given the small sample size, further validation in larger cohorts is essential to confirm LF6's vaccine relevance.</p>","PeriodicalId":101343,"journal":{"name":"Tropical biomedicine","volume":"43 1","pages":"5-15"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147936846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R Ngui, P Johnny, P T Chai, S F N Sidi Omar, S H Lim, T Jinam, K Yaman, T K Tan, K J Lim, N R Seling, S F Jiee
{"title":"Asymptomatic lymphatic filariasis in an elderly patient from Bako, Sarawak: A case report and public health implications.","authors":"R Ngui, P Johnny, P T Chai, S F N Sidi Omar, S H Lim, T Jinam, K Yaman, T K Tan, K J Lim, N R Seling, S F Jiee","doi":"10.47665/tb.43.1.004","DOIUrl":"https://doi.org/10.47665/tb.43.1.004","url":null,"abstract":"<p><p>Lymphatic filariasis (LF) remains a significant public health challenge in many tropical regions where the disease is endemic. In Malaysia, LF is found in small pockets across the country. Asymptomatic carriers play a critical role in transmission but are often undetected. This report details an investigation of an asymptomatic filariasis reported by local health authorities involving an 83-year-old female patient residing in the Bako area, Sarawak. Despite being immobile due to a stroke, routine screening identified an infection with Brugia malayi through microscopy and a rapid diagnostic test. Interestingly, the patient exhibited no acute or chronic symptoms typically associated with filariasis. Contact tracing among her family members revealed that her son was also infected. Both patients received treatment with diethylcarbamazine (DEC) at a dosage of 6 mg/kg, along with albendazole 400 mg and ivermectin 12 mg. Preventive measures included health education, entomological studies, and the implementation of a 'Test & Treat Filariasis' program in the village. By documenting both the index case and a secondary asymptomatic case within the same household, the study provides a strong example of how routine screening and contact tracing can identify hidden sources of infection. This adds significant value to LF elimination strategies and emphasizes the importance of community-level surveillance programs. Coordinated efforts by health authorities, including contact tracing, environmental assessments, and targeted treatment, are essential for controlling the spread of LF and safeguarding public health.</p>","PeriodicalId":101343,"journal":{"name":"Tropical biomedicine","volume":"43 1","pages":"22-25"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147936904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Molecular screening of Anaplasma, Ehrlichia, and Brucella in ticks (Acari: Ixodidae) infesting farm ruminants in Peninsular Malaysia.","authors":"A R Kazim, V L Low, J Houssaini, D Tappe, C C Heo","doi":"10.47665/tb.43.1.005","DOIUrl":"10.47665/tb.43.1.005","url":null,"abstract":"<p><p>Ticks are obligate hematophagous arachnids that parasitize both humans and animals. While considerable research in Malaysia has focused on bacterial detection in ticks, knowledge of tick-borne Anaplasma, Ehrlichia and Brucella in farm ruminants remains limited. In this study, 1,241 ticks comprising of four species (Rhipicephalus microplus, Rhipicephalus haemaphysaloides, Haemaphysalis bispinosa, and Haemaphysalis wellingtoni) were collected from 674 farm ruminants across Peninsular Malaysia. The ticks were pooled and molecularly screened for Anaplasma and Ehrlichia using 16S rRNA gene primers, and Brucella using the BSCP31 gene primer. Out of 130 tick pools, five (3.85%) tested positive for Anaplasma and two (1.54%) for Ehrlichia. No Brucella DNA was detected in all four tick species. All positive pools consisted exclusively of R. microplus, with no pathogens identified in the other three tick species. BLAST analysis revealed that the Anaplasma sequences were identical to Anaplasma marginale, A. platys, and Candidatus \"Anaplasma boleense\", while the Ehrlichia sequences were identical to Ehrlichia ewingii. This study represents the first screening for Anaplasma, Ehrlichia, and Brucella in ticks infesting farm ruminants in Peninsular Malaysia.</p>","PeriodicalId":101343,"journal":{"name":"Tropical biomedicine","volume":"43 1","pages":"26-31"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147936899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A Z Azham, K Jeya Pirathaba, F Franklin, S G Kuppusamy, A Rajamanikam
{"title":"HSP70 gene variants and subtype linked to thermal stress adaptation in Blastocystis sp.","authors":"A Z Azham, K Jeya Pirathaba, F Franklin, S G Kuppusamy, A Rajamanikam","doi":"10.47665/tb.43.1.010","DOIUrl":"10.47665/tb.43.1.010","url":null,"abstract":"<p><p>Blastocystis sp. is the most common enteric protist colonizing a wide range of host and is characterized by wide genotypic diversity. Heat Shock Protein 70 (HSP70), a common stress-response protein has been associated with increased proliferation in Blastocystis sp. under thermal stress. However, the extent of HSP70 genetic variation and its link to thermostability remains unexplored. Our study aims to elucidate HSP70 gene variants among different Blastocystis sp. subtypes, analyze their responses to thermal stress, and evaluate their protease activity following the thermal stress. Heat Shock Protein 70 gene from eighteen Blastocystis sp. isolates of varying subtype - ST1, ST3, ST4, ST6, and ST7 - were amplified, sequenced and phylogenetically analyzed. The cells were then subjected to thermal stress at 42°C for 24 hours and the cell viability was monitored for seven days. Protease activity in solubilized antigens (SA) from purified Blastocystis sp. cells was evaluated following exposure to thermal stress. Phylogenetic analysis revealed two distinct clades: ST4 and ST7 (Clade 1) which are mostly thermotolerant, while ST1, ST3, and ST6 (Clade 2) exhibited lower tolerance. Total protease activity was similar across subtypes, suggesting need for further sub-class specific analysis. Our findings suggests that thermal stress adaptation is subtype dependent and may be influenced by HSP70 variation. This insight highlights the importance of HSP70 as a potential molecular marker for stress adaptation in Blastocystis sp. and underscore the need for deeper investigation of its functional role in parasite persistence and pathogenic potential.</p>","PeriodicalId":101343,"journal":{"name":"Tropical biomedicine","volume":"43 1","pages":"76-82"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147936891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L P Tan, N S Roslan, A R Kazim, C W S Che Wan Zalati, H Hassan, C H Heo
{"title":"Haemaphysalis wellingtoni (Acari: Ixodidae) from the spotted wood owl (Strix seloputo) (Aves: Strigiiformes): a new tick-host record in Peninsular Malaysia.","authors":"L P Tan, N S Roslan, A R Kazim, C W S Che Wan Zalati, H Hassan, C H Heo","doi":"10.47665/tb.43.1.003","DOIUrl":"10.47665/tb.43.1.003","url":null,"abstract":"<p><p>Multiple engorged tick nymphs (n= 6) were collected from an injured spotted wood owl (Strix seloputo) in Kelantan, Peninsular Malaysia. Morphological identification of the nymphs revealed that the ticks were Haemaphysalis wellingtoni, based on several distinctive features: (1) internal edge of palpal article III extending far beyond the internal edge of palpal article II; and (2) four feathery and closespaced infrainternal setae. Subsequent molecular analysis of a randomly selected nymph targeting the mitochondrial 16S gene corroborated with the species identity of the tick. To date, this is first report of the infestation of H. wellingtoni on S. seloputo. Future studies are needed to determine whether native or endemic birds may serve as disseminators of ticks and tick-borne diseases.</p>","PeriodicalId":101343,"journal":{"name":"Tropical biomedicine","volume":"43 1","pages":"16-21"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147936929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S X Chong, V S Lee, W L Choong, N Sahimin, S Abu Bakar, H Y Lee
{"title":"032.","authors":"S X Chong, V S Lee, W L Choong, N Sahimin, S Abu Bakar, H Y Lee","doi":"10.47665/tb.43.1.006","DOIUrl":"10.47665/tb.43.1.006","url":null,"abstract":"<p><p>Hookworm disease is one of the tropical neglected diseases that significantly impacts human health to varying degrees. Hookworms produce various proteins to facilitate host invasion and immune evasion. Despite available treatments, reinfection is common, underscoring the need for effective vaccines. However, the complexity of the hookworm's life cycle poses a challenge in understanding the immune response in the vaccine candidates. Reverse vaccinology (RV) offers a powerful approach to understand the immune response by using various bioinformatics tools. This study begins by identifying hookworm antigens capable of inducing host immune responses, followed by docking analysis with different dendritic cell (DC) receptors to investigate the immunological response of antigenic peptides and further correlated to the immunogenicity findings in clinical trial. Necator americanus GlutathioneS-Transferase-1 (Na-GST-1), a known immunogenic protein from Necator americanus, was selected for docking due to its strong antigenic properties. Fifteen DC receptors were evaluated against Na-GST-1, of which seven receptors (TLR2, TLR3, TLR4, TLR7, DEC-205, CD206, and CD36) exhibited stronger predicted interactions, as indicated by stronger binding affinities with Na-GST-1 utilizing various immunoinformatic tools. These receptors are associated with the mediation of Th1/Th2 immune responses, suggesting a potential correlation between docking affinity and the predicted immunogenicity of Na-GST-1. Overall, this study provides valuable insights into DC receptor-antigen interactions and demonstrate a computational approach for assessing the potential of hookworm antigens to engage DC receptors, thereby supporting rational hookworm vaccine design. These findings support the application of early in silico strategies for advancing vaccine candidates against hookworm infection and strengthening control efforts for neglected tropical diseases.</p>","PeriodicalId":101343,"journal":{"name":"Tropical biomedicine","volume":"43 1","pages":"43"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147936911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Revision of the Simulium (Simulium) multistriatum species-group (Diptera: Simuliidae) in Sumatra, Indonesia: Descriptions of three new species and a redescription of the male and pupa of S. (S.) fenestratum Edwards.","authors":"H Takaoka","doi":"10.47665/tb.43.1.007","DOIUrl":"10.47665/tb.43.1.007","url":null,"abstract":"<p><p>Adults and pupae of black flies assigned to the Simulium (Simulium) multistriatum species-group collected from Sumatra, Indonesia in 1992 and 1994 were reexamined. As a result, three undescribed species were found besides S. (S.) fenestratum Edwards, the only species in this species-group so far described from Sumatra. These undescribed species are described as new: S. (S.) mutaralamense sp. nov., which is characterized in the female by the haired basal portion of the radial vein, in the male by the number of upper-eye (large) facets in 18 or 19 vertical columns and 19 or 20 horizontal rows and hind basitarsus entirely darkened, and in the pupa by the gill with eight filaments widely divergent when viewed laterally; S. (S.) lubuksulasihense sp. nov., which is similar to S. (S.) mutaralamense sp. nov., but differs by the male hind basitarsus yellow on its basal one-third; and S. (S.) liwaense sp. nov., which is characterized in the male by the smaller number of upper-eye (large) facets in 14 or 15 vertical columns and 16 horizontal rows, and in the pupa by the gill with eight filaments moderately divergent when viewed laterally, and all three anterodorsal trichomes unbranched on each side of the thorax. Taxonomic notes to distinguish these new species from their related species are given. The male and pupa of S. (S.) fenestratum are redescribed.</p>","PeriodicalId":101343,"journal":{"name":"Tropical biomedicine","volume":"43 1","pages":"44-59"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147936867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K Abdullah, H Rahman, T Tabassum, A Sadiq, F M Alzahrani, K J Alzahrani, K A Alsharif
{"title":"Fragaria Indica ethanolic extracts: bioactive compounds identification, ADMET analysis and putative inhibitors of bla-TEM beta-lactamase from foodborne bacterial pathogens.","authors":"K Abdullah, H Rahman, T Tabassum, A Sadiq, F M Alzahrani, K J Alzahrani, K A Alsharif","doi":"10.47665/tb.43.1.015","DOIUrl":"10.47665/tb.43.1.015","url":null,"abstract":"<p><p>Fragaria indica stem, leaf, and root extract was used to assess the antimicrobial activity against bla-TEM beta-lactamase producing Shigella flexneri, Salmonella typhi, and Escherichia coli. Ethanolic extracts of F. indica leaves exhibited a maximum zone of inhibition of 20 ± 1.2 mm (p <= 0.001), 18 ± 1.4 mm (p <= 0.001), and 16 ± 1.5 mm (p <= 0.001) against E. coli, S. flexneri, and S. typhi, respectively. To identify different compounds, the bioactive ethanolic leaf extracts were further processed for HPLC, GC-MS, ADMET, and docking analysis. In the ethanolic leaf extract, 19 phenolic compounds were identified in HPLC analysis. Three phenolic compounds, including Isorhamnetin-3-rutinoside, 5, 7-Dihydroxy-4' -methoxyflavone, and Luteolin, were for the first time reported in F. indica. In GC-MS analysis, sixteen compounds were identified. From the literature search, among the identified compounds, AlphaHimachalene, 1,3-Diphenyl-1-((trimethylsilyl)oxy)-1(Z)-heptene, 1H-Benzocycloheptene, Bicyclo[5.2.0] nonane, cis-1,1,3,4-Tetramethylcyclopentane, Bicyclo[2.2.2]octane-cis-2,3-diyl Carbonate, BetaHimachalene and 2-methylene-4,8,8-trimethyl-4-vinyl were reported for the first time in F. indica. Two compounds, including Alpha-Himachalene and Bicyclo[2.2.2]octane-cis-2,3-diyl carbonate, having good water solubility, drug likeness, and medicinal characteristics, were selected for docking analysis. Docking of Alpha-Himachalene and Bicyclo[2.2.2]octane-cis-2,3-diyl carbonate showed interaction with Pro-26, Phe-22, and Ala-23 residues of bacterial bla-TEM beta-lactamase. Similarly, Bicyclo[2.2.2] octane-cis-2,3-diyl carbonate interacts with amino acid residues of Ala-235 and Ser-233 of bla-TEM beta-lactamase. Further studies will help to characterize the anti-infective compounds against bla-TEM producing foodborne bacterial pathogens.</p>","PeriodicalId":101343,"journal":{"name":"Tropical biomedicine","volume":"43 1","pages":"132-141"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147936907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The insecticide resistance status of Anopheles mosquitoes in the rice agroecosystems of Anambra State, Nigeria.","authors":"C B Ukonze, C K Ezihe, C M Egbuche, H A Hasan","doi":"10.47665/tb.43.1.011","DOIUrl":"10.47665/tb.43.1.011","url":null,"abstract":"<p><p>Malaria remains one of the leading causes of death worldwide, particularly in Africa, where various control interventions such as case management, insecticide-treated nets (ITNs), intermittent preventive treatment in pregnant women and infants, and indoor residual spraying (IRS) have been implemented. Insecticide resistance in malaria vectors poses a major challenge to vector control efforts. This study assessed the insecticide resistance status of Anopheles gambiae s.l. populations in rice agroecosystems of Anambra State, Nigeria. Mosquito larvae were sampled from four rice-farming clusters in Anambra state, reared to adulthood at the National Arbovirus and Vector Research Center (NAVRC) and tested using the WHO susceptibility bioassay against four insecticides namely dichloro-diphenyl-trichloroethane (DDT), pirimiphos-methyl, bendiocarb, and deltamethrin. Knockdown resistance (kdr) mutations were also analyzed. Results revealed confirmed resistance to DDT and deltamethrin, likely due to past agricultural use of DDT and cross-resistance with pyrethroids, which are widely used in ITNs and IRS. However, An. gambiae s.l. populations remained susceptible to bendiocarb and pirimiphos-methyl, except in Umunze, where resistance to pirimiphos-methyl was detected. The L1014F kdr mutation was detected at varying frequencies across locations, a key genetic marker for resistance to pyrethroids and DDT, in both An. gambiae s.s. and An. coluzzii. These findings highlight the importance of continuous insecticide resistance monitoring in rice agroecosystems, improved pesticide regulations and the implementation of integrated vector control management to slow down the spread of resistance in malaria vectors in Anambra.</p>","PeriodicalId":101343,"journal":{"name":"Tropical biomedicine","volume":"43 1","pages":"83-89"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147936944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Eschars and estate fever: A case series from the Johorean oil palm heartland highlighting the changing face of scrub typhus in Malaysia.","authors":"B T Yew, L Y S Nathanael, N H Yahya","doi":"10.47665/tb.43.1.009","DOIUrl":"10.47665/tb.43.1.009","url":null,"abstract":"<p><p>Scrub typhus, a zoonotic bacterial infection caused by the arthropod-borne, Gram-negative, obligate intracellular bacillus Orientia tsutsugamushi and transmitted by larval chiggers, is an underdiagnosed cause of acute undifferentiated febrile illness. Its clinical spectrum ranges from a self-limited denguelike illness to rapidly progressive multiorgan dysfunction driven by smallvessel vasculitis, including pneumonitis, acute kidney injury, hepatitis, encephalitis and circulatory shock. Early recognition is frequently missed because the characteristic eschar may be absent or easily overlooked in concealed or pigmented skin sites, and definitive diagnostics such as polymerase chain reaction (PCR) or indirect immunofluorescence assay (IFA) are often unavailable in resource-limited settings. Occupational and environmental exposures, particularly work in oil palm or rubber plantations and contact with forest- estate ecozones, remain key epidemiological clues that may be under-elicited in routine clinical practice. We report a case series of four patients with confirmed scrub typhus presenting to a hospital in Kluang district, Johor, Malaysia. All patients had acute fever and non-specific viral-like symptoms, including malaise, chills, headache and myalgia. Thrombocytopenia and acute kidney injury occurred in 50%, while 75% demonstrated transaminitis. Eschars were identified in all patients following comprehensive dermatological examination. Diagnosis was confirmed by PCR for O. tsutsugamushi DNA, a fourfold rise in IFA titres, or a single high-titre IgM or IgG in a compatible clinical syndrome. Three patients (75%) had clear domiciliary or occupational risk factors, including oil palm work or residence near secondary scrubland. One patient developed organ-threatening complications with acute kidney injury and severe hepatitis, illustrating the vasculitic end-organ involvement of severe scrub typhus. All patients achieved clinical defervescence and symptomatic improvement within 24-48 hours of doxycycline initiation, consistent with the characteristic brisk antimicrobial response. This series underscores the need for a low threshold of clinical suspicion and early empiric rickettsial coverage in undifferentiated febrile illness with relevant exposure in rural Malaysia and highlights the need for larger multicentre studies to define predictors of severity, guide triage and inform prevention in high-risk land-use settings.</p>","PeriodicalId":101343,"journal":{"name":"Tropical biomedicine","volume":"43 1","pages":"65-75"},"PeriodicalIF":0.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147936924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}