American Journal of Tropical Medicine and Hygiene最新文献

{"title":"Another Dengue Antiviral Drug Bites the Dust Early: Where does Dengue Therapeutic Drug Development Go from Here?","authors":"Swee Sen Kwek, Jenny G Low","doi":"10.4269/ajtmh.25-0362","DOIUrl":"https://doi.org/10.4269/ajtmh.25-0362","url":null,"abstract":"","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144607170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Far from the Familiar: My First Encounter with Chagas.","authors":"Ozioma Esther Onuselogu","doi":"10.4269/ajtmh.25-0234","DOIUrl":"https://doi.org/10.4269/ajtmh.25-0234","url":null,"abstract":"","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144607171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Worker's Struggle.","authors":"Sakan Binte Imran, Shadman Mahmood Khan Pathan","doi":"10.4269/ajtmh.25-0111","DOIUrl":"https://doi.org/10.4269/ajtmh.25-0111","url":null,"abstract":"","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144607169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial and Temporal Analyses of Melioidosis in Kaohsiung, Taiwan.","authors":"Kuang-Yueh Chen, Kuang-Ying Chen, Hsin-Ping Hu, Bing-Mu Hsu, Duen-Wei Hsu, Yao-Shen Chen, Hsi-Hsun Lin, Chung-Yuan Ren","doi":"10.4269/ajtmh.24-0854","DOIUrl":"https://doi.org/10.4269/ajtmh.24-0854","url":null,"abstract":"<p><p>Melioidosis, a fatal infectious disease caused by the saprophytic bacterium Burkholderia pseudomallei, is endemic to Kaohsiung, Taiwan. To assess potential exposure to the pathogen among residents, seropositivity to the B. pseudomallei flagella protein was measured, revealing an overall positivity rate of 14.6%, with peak rates observed in individuals ages 10-19 and 80-99 years old. Geographical analysis identified seropositivity clusters (>16%) spanning northern, central, and southern Kaohsiung, whereas clinical cases were concentrated in the northern (Qieding district) and central regions (Zuoying and Nanzi districts). Spatial autoregression using the Moran I revealed a prominent central cluster, with SaTScan and Ripley K function analyses confirming cluster radii of 6.2-8.8 and 6.4-6.7 km, respectively. These clusters encompassed Zihguag, Nanzi, and Zuoying districts, where 454,000-513,000 residents were potentially exposed to B. pseudomallei over a 20-year period (2003-2024). Melioidosis incidence peaked in 2005 (8.5 cases per 100,000 people), 2009-2011 (15.6-23.4 cases per 100,000 people), and 2024 (28.2 cases per 100,000 people), coinciding with catastrophic typhoons. Annual melioidosis incidence within the hot spot correlated with rainfall intensity during typhoon events. Flooded areas caused by typhoons overlapped with the hot spot, inundating 38-43% of the region. Higher B. pseudomallei polymerase chain reaction positivity rates (11-22%) were detected in northern rivers flowing through the hot spot compared with lower rates (0-7%) in southern or eastern nonhot-spot areas. These findings suggest that typhoon-related flooding may contribute to the formation of melioidosis hot spots in Kaohsiung.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144607175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Imported Malaria Outbreak in Military Personnel Returning from Peacekeeping Operation in South Sudan - Thailand, 2023.","authors":"Anupong Sirirungreung, Parichat Sangwanborirak, Kasinpiti Naprasith, Kanlaya Jongcherdchootrakul, Porruthai Kittikanara, Watcharee Yokanit, Sutchana Tabprasit, Adisorn Lumpaopong, Ram Rangsin, Mathirut Mungthin","doi":"10.4269/ajtmh.24-0735","DOIUrl":"https://doi.org/10.4269/ajtmh.24-0735","url":null,"abstract":"<p><p>Malaria remains a global health concern, with Thailand primarily experiencing cases in border areas and from imported infections. During the third rotation of Thai peacekeeping troops returning from South Sudan between June and November 2023, a malaria outbreak was reported. In response to the outbreak, we conducted a retrospective cohort study, in which we identified 46 confirmed cases of malaria, with 27 occurring postdeployment. The most common species were Plasmodium falciparum (n = 19) and Plasmodium ovale (n = 16), with a median postdeployment time to first symptom of 14 weeks (interquartile range: 9-28). The analysis revealed that those relying on informal sources for malaria knowledge, such as friends, were at higher risk (hazard ratio: 4.92; 95% CI: 1.97-12.28). Challenges with prophylaxis adherence and glucose-6-phosphate dehydrogenase deficiency-related hemolysis were identified. This study calls for improved malaria prevention in South Sudan, better postdeployment monitoring, enhanced education for troops, and research on terminal prophylaxis to reduce cases.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144607172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Panton-Valentine Leukocidin Genes and Staphylococcal Cassette Chromosome Mec Types in Methicillin-Resistant Staphylococcus aureus That Causes Hospital- and Community-Acquired Infections.","authors":"Faiqa Arshad, Iqbal Hussain Dogar, Kokab Jabeen, Zill-E- Huma, Romeeza Tahir, Sidrah Saleem, Waleed Tariq, Muhammad Junaid Tahir, Afsana Ansari Shaik, Muhammad Sohaib Asghar","doi":"10.4269/ajtmh.24-0452","DOIUrl":"https://doi.org/10.4269/ajtmh.24-0452","url":null,"abstract":"<p><p>This cross-sectional descriptive study was conducted at the University of Health Sciences, Lahore, over 5 years (2016-2020) to explore the association of Panton-Valentine leucocidin (pvl) genes and staphylococcal cassette chromosome mec (SCCmec) types with hospital-acquired (HA) and community-acquired methicillin-resistant Staphylococcus aureus (MRSA). Panton-Valentine leucocidin genes in MRSA have been found in HA-MRSA strains, thereby raising the prevalence of highly virulent and resistant strains. Furthermore, the usage of staphylococcal cassette chromosome mec (SCCmec) typing is crucial for understanding the epidemiology and evolution of MRSA. The isolates of Staphylococcus aureus were acquired from clinical samples of the patients. Gram staining, catalase, coagulase, and DNAse tests were used for S. aureus confirmation. The methicillin resistance genes A and C (mecA and mecC) genes were detected to confirm MRSA by using a 30 µg cefoxitin disk. Panton-Valentine leucocidin gene identification and SCCmec typing (types I-V and XI) were conducted through polymerase chain reaction testing. Only 440 strains of MRSA were isolated, and 31.6% were positive for the pvl gene. The most prevalent SCCmec type among the MRSA isolates was type III, which was found in 42.7% of isolates. The pvl gene was detected in 74% of SCCmec types IV and V and in only 14% of SCCmec types I, II, III, and IIIA. This study revealed the dynamic adaptability of MRSA strains within healthcare settings, with the cooccurrence of the pvl gene and various SCCmec types highlighting the complexity of MRSA epidemiology. The urgent implementation of comprehensive strategies that integrate molecular surveillance and infection control measures is crucial for mitigating MRSA.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144607173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Safety, Pharmacokinetics, and Activity of AT-752, a Novel Nucleotide Prodrug with Pan-Serotype Activity against Dengue Virus: A Phase 2, Randomized, Double-Blind Study.","authors":"Arantxa Horga, Mauro M Teixeira, Swapnav Borthakur, Shannan Lynch, Janice Chin, Laura Ishak, Xiao-Jian Zhou, Keith Pietropaolo, Bruce Belanger, Yang Lei, Qi Huang, Janet Hammond","doi":"10.4269/ajtmh.24-0696","DOIUrl":"https://doi.org/10.4269/ajtmh.24-0696","url":null,"abstract":"<p><p>AT-752 is a novel guanosine nucleotide prodrug inhibitor with pan-serotype antiviral activity against dengue virus. In this phase 2, randomized, double-blind, placebo-controlled study, we evaluated the activity, safety, and pharmacokinetics of oral AT-752 (750 mg thrice daily for 5 days) compared with a placebo in 21 adults with confirmed dengue infection. The primary endpoint was the change from baseline in viral load via reverse transcription quantitative polymerase chain reaction testing, with assessments performed daily on Days 1-8, 14, and 28. The primary endpoint was nonevaluable because many patients presented late during the course of disease, with low baseline viremia levels precluding accurate quantification at subsequent timepoints. In the as-treated population (patients with assessment at baseline and at each post-baseline timepoint), the numerical mean reduction (versus baseline) in viral load on Day 4 was greater in the AT-752 group than the placebo group (P = 0.0022). The median time to a sustained resolution of fever (the major clinical sign of dengue) was 4 days in the AT-752 group compared with >5 days in the placebo group; the reduction in oral temperature at the Day 4 timepoint was greater in the AT-752 group (treatment difference: 0.84°C; P = 0.0322). There was a trend toward faster platelet recovery in the AT-752 group compared with the placebo group, and proportionally fewer patients in the AT-752 group underwent hospitalization for disease progression (one patient in each group). AT-752 exhibited favorable safety and tolerability; the majority of adverse events were mild or moderate, and Grade 3 or 4 adverse events occurred at similar rates in both groups. These data support the further evaluation of AT-752 in treating dengue in future clinical trials.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144607174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crimean-Congo Hemorrhagic Fever Outbreak in Podor, Northern Senegal in 2022: Two Independent Emergences and Unprecedented Mortality.","authors":"Ousseynou Sene, Samba Niang Sagne, Déthié Ngom, Mamoudou Bocoum, Mamadou Korka Diallo, Aliou Khoulé, Elisabeth Thérèse Faye, Sokhna Mayemouna Diop, Idrissa Diallo, Cheikh Loucoubar, Mawlouth Diallo, Ndongo Dia, Yoro Sall, Boly Diop, Mamadou Ndiaye, Amadou Alpha Sall, Manfred Weidmann, Moussa Moise Diagne, Malick Fall, Ousmane Faye, Oumar Faye, Etienne Simon-Lorière, Diawo Diallo, Mamadou Aliou Barry, Gamou Fall","doi":"10.4269/ajtmh.24-0445","DOIUrl":"https://doi.org/10.4269/ajtmh.24-0445","url":null,"abstract":"<p><p>Crimean-Congo hemorrhagic fever (CCHF) is a lethal zoonotic disease transmitted through tick bites and contact with infected animals or humans. As CCHF continues to expand worldwide, we report on the first severe outbreak in Senegal (Podor, Saint-Louis region) in 2022. We conducted a comprehensive outbreak investigation after a confirmed CCHF human case in Podor. This included sample collections from humans, animals, and ticks from the household and surrounding area. Human and animal samples were tested by ELISA for antibodies to CCHF virus and by reverse transcription polymerase chain reaction (RT-PCR) for CCHF virus RNA, whereas tick samples underwent CCHF RT-PCR only. Positive RT-PCR samples underwent viral genome sequencing for genetic characterization. We determined three CCHF human cases, with two deaths, as well as virus circulation in 11 ticks and in livestock, with an overall seroprevalence of 42.5%. CCHF IgG antibodies were detected in human contact cases, showing its prior prevalence in the area. Phylogenetic analyses revealed high genetic diversity within CCHF genotypes, with existence of reassortants and cocirculation of two different isolates from various origins in Mboyo and Nenette villages, where human cases were detected. The data showed a correlation between the strains identified in humans and ticks in each village, showing two independent emergences in Podor. The outbreak in Podor was probably because of the high abundance of animal hosts in this sylvopastoral area, the diversity of tick populations with the presence of the main CCHF vectors, and the increasing prevalence of CCHF virus. The surveillance in this area needs to be strengthened.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144590283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Widespread Soil-Transmitted Parasitic Contamination in Raw Vegetables at Fresh Markets in the Inner Zone of Bangkok: Findings from a Cross-Sectional Study.","authors":"Atthapon Pidsaya, Korawit Kanjana, Kwannan Nantavisai","doi":"10.4269/ajtmh.25-0044","DOIUrl":"https://doi.org/10.4269/ajtmh.25-0044","url":null,"abstract":"<p><p>Bangkok, a globally popular travel destination, hosts numerous fresh markets and street food vendors catering to locals and visitors. Although raw vegetables are integral to Thai cuisine, their consumption may pose risks of soil-transmitted parasitic infections. This cross-sectional study assessed the prevalence of parasitic contamination in raw vegetables from Bangkok's inner zones, focusing on five districts: Huai Khwang, Khlong Toei, Pathum Wan, Chatuchak, and Phra Nakhon. A total of 200 samples across eight vegetable types were randomly collected from these areas and prepared for analysis using sedimentation techniques followed by microscopic examination. Observers conducting the microscopy were blinded and operated independently to minimize bias. The overall prevalence of parasitic contamination was 77% (n = 154/200). The highest contamination levels were in Huai Khwang and Chatuchak (90%, P <0.05). Identified contaminants included Strongyloides stercoralis larvae (57%), hookworm eggs (20%), Ascaris lumbricoides eggs (16%), Trichuris trichiura eggs (12%), Toxocara spp. eggs (10%), and others. Chinese cabbage was significantly more contaminated with hookworm eggs (P <0.0001) and T. trichiura eggs (P <0.001) than other vegetables, although less so with S. stercoralis (P <0.0001). These findings highlight raw vegetables as potential sources of parasitic infections. Consumers are advised to thoroughly wash vegetables before consumption, whereas vendors should wear gloves to minimize exposure to skin-penetrating parasites. Prophylactic antiparasitic treatment, particularly for children and immunocompromised individuals, is recommended annually.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144590258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal Trends and Characteristics of Community-Based HIV Testing: First Community-Based Testing Program Results of Men Who Had Sex with Men and Female Sex Workers in Haiti, 2015-2018.","authors":"Tristan Alain, Maxime Inghels, Jean-Mary Mérisier, Vialli Dimanche, Guillemette Quatremère, Candice Audemard, Sabine Lustin, Charlot Jeudy, Arnoux Descardes, Daniela Rojas Castro, David Michels","doi":"10.4269/ajtmh.24-0391","DOIUrl":"https://doi.org/10.4269/ajtmh.24-0391","url":null,"abstract":"<p><p>To increase HIV status awareness among men who have sex with men (MSM) and female sex workers (FSWs), a community-based HIV testing program was implemented for the first time in Haiti. We aimed to assess 1) the effectiveness of the program to reach HIV-exposed populations over time and 2) the characteristics, HIV exposure, and testing profile of program participants. Rapid diagnostic HIV testing (RDT) was offered to all individuals present in several community-based settings across Haiti. Trends in the number of tested individuals, first-time tested, and HIV positive tested per intervention were described using linear regression. Characteristics and factors related to the first-time test were described. Between July 2015 and April 2018, 445 interventions in 91 community-based venues resulted in 3,998 rapid tests performed. A median of eight individuals was tested per intervention, with 18% first-time testers and 6% with HIV-positive results. The overall numbers of tests and positive test results increased over the intervention program period. Within 1,572 first-time RDT testers (1,216 MSM, 235 FSWs, and 121 nonkey population), 31% (n = 489) were first-time HIV testers. First-time tested individuals reported HIV exposure, such as lack of condom use at last intercourse (33%), transactional sex (35%), and recent (≤12 months) sexually transmitted infection (12%). The community-based HIV testing program effectively reached HIV-positive and previously untested individuals over a 3-year period. Continued community-based testing in conjunction with other HIV testing services is recommended for Haiti.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144590257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}