American Journal of Tropical Medicine and Hygiene最新文献

{"title":"Bilateral Necrotic Foot Lesions of Kaposi Sarcoma in a Man from Ecuador.","authors":"Su M Aye, Nathan Asher, Glen Blackman, Stephen L Walker","doi":"10.4269/ajtmh.25-0755","DOIUrl":"https://doi.org/10.4269/ajtmh.25-0755","url":null,"abstract":"","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147484394","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":"Geographical Heterogeneity in Antimalarial Resistance Markers by Genomic Surveillance in Angola, 2023.","authors":"Maria Florinda João, Andrés Aranda-Díaz, Faith De Amaral, Takalani I Makhanthisa, Sonja B Lauterbach, Mukosha Chisenga, Brighton Mangena, Paulo Maquina, Isobel Routledge, Chadwick Sikaala, John Chimumbwa, Domingos Jandondo, José Franco Martins, Jaishree Raman, Jennifer L Smith, Pedro Rafael Dimbu","doi":"10.4269/ajtmh.25-0226","DOIUrl":"10.4269/ajtmh.25-0226","url":null,"abstract":"<p><p>Plasmodium falciparum malaria remains a leading cause of mortality in Angola, with emerging antimalarial resistance threatening treatment and prevention strategies. Efficacy of artemether-lumefantrine has been reported below 90% in two provinces, underscoring the need for routine resistance surveillance. This study aimed to provide a geographically comprehensive and up-to-date overview of antimalarial drug resistance markers in Angola. Between March and July 2023, dried blood spots and demographic data were collected from P. falciparum-positive participants at 14 health facilities across 7 provinces. Multiplexed amplicon sequencing was used to characterize single nucleotide polymorphisms in 12 genes linked with resistance, estimate allele frequencies, and detect coinfecting non-falciparum Plasmodium species. Sequence data from 820 samples revealed significant geographic variation in resistance markers. In the southeast, artemisinin partial resistance markers (k13 P574L, P441L) were detected at very low prevalence (<0.1%), whereas the quintuple dhps/dhfr haplotype, linked to sulfadoxine-pyrimethamine resistance, was very prevalent (>35% of samples). In the northwest, the sextuple dhps/dhfr haplotype, a marker of higher sulfadoxine-pyrimethamine resistance, was most prevalent in the Zaire province (14.2%). The chloroquine resistance marker crt C72/V73/M74I/N75E/K76T (CVIET) haplotype had a national prevalence of 17.7%, detected in over 48% of samples from the northern sites. The mdr1 N86 genotype, linked to reduced lumefantrine susceptibility, was detected in 99.2% of samples. Coinfections of P. falciparum and non-falciparum species were rare, with no Plasmodium vivax coinfections detected. These findings highlight the need for continued monitoring to safeguard treatment efficacy, reinforcing the importance of molecular surveillance in malaria control strategies.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147472541","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":"Rapid Behavioral Assessment of Knowledge, Attitudes, and Practices on Dengue Fever to Inform Risk Communication and Community Engagement Efforts in the Kingdom of Tonga.","authors":"Patelisio P Patelisio, Seini Toumoua Fifita, Nanise Fifita, Mele Tilema Cama, Mohammad Alamgir, Johary Randimbivololona","doi":"10.4269/ajtmh.25-0583","DOIUrl":"10.4269/ajtmh.25-0583","url":null,"abstract":"<p><p>In February 2025, Tonga's Minister of Health declared a national dengue fever epidemic, emphasizing the urgent need to raise public awareness and implement preventative measures. In response to this declaration, a study was conducted from March to May 2025 to investigate the sociodemographic determinants affecting dengue fever awareness and preventative behaviors across Tonga's primary islands: Tongatapu, Ha'apai, and Vava'u. Researchers conducted a survey of 140 randomly selected households, achieving a 93% response rate. The results revealed that although 90% of respondents were aware of dengue fever, 67% had limited knowledge of its transmission and prevention. A multivariable analysis revealed that awareness levels were significantly higher among individuals with at least a secondary education, those who regularly listened to radio broadcasts, and those who classified dengue fever as \"very serious.\" Focus group discussions further illuminated community misconceptions about dengue fever symptoms, which were often mistaken for those of respiratory conditions. Participants also expressed concerns about a noticeable decrease in the frequency of health officials' home visits since the onset of the coronavirus disease 2019 pandemic. Community members advocated bolstering local engagement strategies, including the utilization of community radio, village committees, and targeted networks for mothers and youth. These findings underscore the necessity for effective communication strategies, including Tongan-language radio dramas, to enhance community health resilience and encourage sustained preventative practices.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"956-960"},"PeriodicalIF":1.6,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13153620/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147472530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Entamoeba histolytica: Diagnostic Microscopy in Clinical Amoebiasis.","authors":"Devyani Sharma, Divya Rattan, Rakesh Sehgal","doi":"10.4269/ajtmh.26-0105","DOIUrl":"https://doi.org/10.4269/ajtmh.26-0105","url":null,"abstract":"","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147472436","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":"Emerging Artemisinin Partial Resistance in Southern Africa.","authors":"Rosario Martinez-Vega, Deus S Ishengoma, Roly Gosling","doi":"10.4269/ajtmh.25-0417","DOIUrl":"https://doi.org/10.4269/ajtmh.25-0417","url":null,"abstract":"<p><p>A new focus of probable artemisinin-partial resistance (ART-R) has been identified in southern Africa, driven by the P441L mutation in the Plasmodium falciparum Kelch13 gene. This emerging cross-border cluster across Angola, Namibia, and Zambia represents the fourth major ART-R focus identified in Africa, adding to the previously reported foci in East Africa and the Horn of Africa. Findings from three new studies reveal 7.3%, 33%, and 47% prevalence of P441L in specific sites in Angola, Namibia, and Zambia, respectively. The Genomics of Malaria in the Elimination 8 project enabled harmonized, real-time molecular surveillance across five countries, providing actionable data for national malaria programs. Given past failures to contain chloroquine and sulfadoxine-pyrimethamine resistance, a timely response is critical. We recommend immediate treatment policy shifts, expanded surveillance, and regional coordination to prevent the spread of ART-R. This Perspective calls on global health actors to act decisively while resistance remains geographically limited.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147472433","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":"Association between HbA1c Levels and Clinical Outcomes in Patients with Diabetes Mellitus and Melioidosis.","authors":"Sam Guempel-Crothers, Stuart Campbell, Mirjam Kaestli, Celeste Woerle, Mark Mayo, Ella M Meumann, Bart J Currie","doi":"10.4269/ajtmh.25-0454","DOIUrl":"10.4269/ajtmh.25-0454","url":null,"abstract":"<p><p>Diabetes mellitus (DM) is the major clinical risk factor for melioidosis, though the effect of improved glycemic control on clinical outcomes is unknown. We investigated whether glycemic control affects clinical outcomes by analyzing a composite outcome of death or intensive care unit admission among patients from the Darwin Prospective Melioidosis Study, stratified by their glycosylated hemoglobin (HbA1c). A total of 292 patients with melioidosis and DM were identified with mean HbA1c of 10.2% (95% CI: 9.8-10.4). The composite outcome occurred in 74 (24.3%) patients, but it was not associated with HbA1c when analyzed by quartiles (P = 0.48) or as a continuous variable (P = 0.41). As in other studies, bacteremia remained the strongest factor associated with adverse outcomes (odds ratio: 9.68, 95% CI: 4.15-22.58, P <0.01). Unlike in other studies, age ≥50 years trended toward protection from death/ICU (P = 0.08). These data reflect continuing gaps in understanding the complex interplay of the immune system, DM, and melioidosis.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"844-847"},"PeriodicalIF":1.6,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13153589/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147472448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevalence of Coinfection with Malaria and Intestinal Helminths among School-Aged Children in Nwoya District, Northern Uganda: A Cross-Sectional Study.","authors":"Kiel McGowan, Felix Bongomin, Donald Otika, Cameron O'Connell, Nicholas Matejak, Davidson H Hamer","doi":"10.4269/ajtmh.25-0647","DOIUrl":"10.4269/ajtmh.25-0647","url":null,"abstract":"<p><p>There is dual endemicity of malaria and helminthic infections in low- and middle-income countries. Coinfection with both infectious diseases may have compounding negative effects on the health of school-aged children (SAC) in endemic areas. The prevalence of coinfection with malaria and intestinal helminths, including soil-transmitted helminths, Schistosoma mansoni, and Hymenolepis nana, was assessed among SAC in rural northern Uganda. A school-based cross-sectional study was conducted at four randomly selected schools from June 2 to June 10, 2025 in Nwoya District, Uganda. Children aged 5-18 years provided stool and blood samples, and were surveyed to assess demographic, environmental, and health-related factors. Intestinal helminth diagnosis was performed using a modified Kato-Katz method (Odongo-Aginya stain); malaria was detected using Plasmodium falciparum (P. falciparum) histidine-rich protein 2 rapid diagnostic tests (RDTs) and blood smears. Overall, 190 SAC with a median age of 13 years were enrolled. Although 75.3% (n = 143) of SAC tested positive for P. falciparum on an RDT, only 13.2% (n = 25) had microscopically detected parasitemia. Intestinal helminth infections were uncommon and involved Ascaris lumbricoides (0.5%; n = 1), Hymenolepis nana (1.6%; n = 3), and Schistosoma mansoni (1.1%; n = 2). All SAC with intestinal helminth infections (3.2%; n = 6) had positive malaria RDT results. The high rate of malaria RDT positivity with negative blood smears may be due to persistent antigenemia post-treatment or false negative blood smear results due to chronic low-grade parasitemia. The low rate of malaria-helminth coinfection among SAC observed in the present study is supported by other recent studies in Uganda and suggests a high efficacy of national mass drug administration programming for the control of intestinal helminths.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"913-922"},"PeriodicalIF":1.6,"publicationDate":"2026-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13153617/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147442275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Treatment of New World Mucosal Leishmaniasis: Randomized Comparison of Glucantime®, Liposomal Amphotericin B, and Miltefosine.","authors":"Jaime Soto, Paula Soto, David Paz, Daniela Rivero, Martha Sánchez, Maria Arteaga, Jonathan Berman","doi":"10.4269/ajtmh.25-0619","DOIUrl":"10.4269/ajtmh.25-0619","url":null,"abstract":"<p><p>New World Mucosal Leishmaniasis (ML) is predominantly caused by Leishmania braziliensis. We performed the first randomized trial of the three recommended agents for this disease-intravenous pentavalent antimony (Sb), intravenous liposomal amphotericin B (LAMB), oral miltefosine-with 24-month follow-up. Upon study enrollment, disease was scored by the number of sites (oro-nasal-palate, pharynx, larynx) and degree of disease at each site (maximum score = 60.) Our criterion for \"cure\" was ≥90% diminution in the enrollment score. Cure rates were 20/40 (50%) for Sb, 18/40 (45%) for LAMB, and 23/40 (57%) for miltefosine. Cure was highly dependent on whether the patient was being treated for the first time (39/55 = 71% cure) or undergoing repeat treatment (22/63 = 35% cure). The primary reason for the low cure rate for repeat patients was laryngeal disease at enrollment. For all patients, naïve patients, and repeat patients, the miltefosine cure rate was highest but not statistically so. A curative score at 2-6 months of follow-up had a predictive value of 94% for cure. It is notable that 14 of the 57 treatment failures (25%) were attributable to relapses occurring more than 24 months after therapy completion. Myalgias/arthralgias/general bodily discomfort occurred for LAMB and Sb patients; diarrhea and motion sickness occurred for miltefosine patients; Electrocardiogram abnormalities (occasionally severe) were seen in LAMB and Sb patients. When choosing a treatment of a ML patient, cure rates in part based on disease location and absence/presence of previous treatment, route of administration, tolerability, and cost should be considered. Patients should be followed for ≥2 years.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"874-881"},"PeriodicalIF":1.6,"publicationDate":"2026-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13153632/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147442315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevalence and Resistance Patterns of Pseudomonas aeruginosa in a Tunisian Intensive Care Unit.","authors":"Olfa Gargouri, Karama Bouchaala, Nourelhouda Ben Ayed, Sirine Koubaa, Fahmi Smaoui, Chokri Ben Hamida, Hela Karray Hakim, Mabrouk Bahloul","doi":"10.4269/ajtmh.25-0161","DOIUrl":"10.4269/ajtmh.25-0161","url":null,"abstract":"<p><p>Pseudomonas aeruginosa is a major cause of health care-associated infections, particularly in intensive care units (ICUs). To the best of our knowledge, this is one of the rare studies reporting the prevalence and antimicrobial resistance patterns of P. aeruginosa in a Tunisian ICU. This retrospective study included all P. aeruginosa strains isolated from ICU patients in Sfax, Tunisia, between 2017 and 2024. A total of 1,126 nonredundant P. aeruginosa strains were obtained from 767 patients. P. aeruginosa strains accounted for 21.1% of all clinical isolates in the ICU. The majority of strains were isolated from respiratory samples (54.6%) and blood cultures (14.3%). The prevalence of resistance rates was highest for ticarcillin (48.3%) and ticarcillin-clavulanic acid (48.6%). The resistance to both ceftazidime and imipenem was observed in 33.6% of P. aeruginosa strains. The prevalence of resistance of P. aeruginosa was 29.8% and 26.2% to ceftazidime-avibactam (CAV) and ceftolozane-tazobactam (C/T), respectively. The prevalence of resistance to amikacin and ciprofloxacin was 36.2% and 37.9%, respectively. Of the 1,126 isolates, 346 (30.7%) were multidrug-resistant P. aeruginosa (MDR-PA) strains, presenting resistance to ceftazidime, ciprofloxacin, and amikacin simultaneously. Since 2022, a significant increase in the MDR rate was observed, reaching 46.3% in 2024 (P <0.001). The resistance rates of MDR-PA were 52.5% and 56.8% to C/T and CAV, respectively. None of the tested MDR-PA strains showed resistance to colistin. This study highlights a high prevalence of MDR strains of P. aeruginosa in our ICU, with increasing resistance over recent years. Prevention is highly warranted.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"837-843"},"PeriodicalIF":1.6,"publicationDate":"2026-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13153622/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147430324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Clinico-Microbiological Profile of Patients with Acute Cholangitis.","authors":"Souradeep Chowdhury, Sagnik Biswas, Soumya J Mahapatra, Deepak Gunjan, Ankur Goyal, Hitender Gautam, Bimal Kumar Das, Raju Sharma, Sanjeev Sinha, Benu Dhawan","doi":"10.4269/ajtmh.25-0488","DOIUrl":"10.4269/ajtmh.25-0488","url":null,"abstract":"<p><p>The aim for the present study was to determine the clinico-microbiological profile and antimicrobial susceptibility patterns of organisms isolated from bile aspirates during endoscopic retrograde cholangiopancreatography (ERCP) in patients with acute cholangitis. In this prospective, observational, single-center study, bile aspirates and blood from consecutive patients undergoing ERCP for acute cholangitis were collected for culture. Demographic, outcome, and microbiological data were collected. Multivariate logistic regression was used to identify factors associated with adverse outcomes. Bile aspirates from 117 patients were collected; 95 (81.2%) yielded positive culture results, and 101 isolates were identified. Gram-negative organisms were the most frequently isolated, with Escherichia coli (E. coli; 50.5%), Pseudomonas spp. (21.8%), and Klebsiella spp. (15.8%), being the most common. Extended-spectrum beta-lactamase production and carbapenem resistance were observed in 79.1% and 29.2% of Gram-negative isolates, respectively. Among 64/117 (54.7%) concurrent blood cultures, 11 (17.2%) were positive. A biliary endoscopic sphincterotomy had been conducted previously in 43 cases (36.8%) and was associated with a higher frequency of E. coli and carbapenem-resistant Klebsiella pneumoniae (CRKP). Multivariate analysis revealed that male sex (odds ratio [OR]: 4.2; P = 0.05) and malignant biliary obstruction (OR: 8.1; P = 0.005) were independently associated with worse outcomes. Bile cultures frequently yield multidrug-resistant organisms in acute cholangitis. A previous biliary sphincterotomy increases the risk of drug-resistant infections, particularly CRKP. These findings highlight the importance of local microbiological surveillance and individualized empirical therapy.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"832-836"},"PeriodicalIF":1.6,"publicationDate":"2026-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13153633/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147430333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}