American Journal of Tropical Medicine and Hygiene最新文献

{"title":"Ulceronecrotic Eschar as a Cutaneous Clue to Disseminated Melioidosis.","authors":"Venkateswaran Ramanathan, Deepti Singh, Gayathri Premalatha Jaganathan, Amit M Kamat, Monisha Gopal Aswath, Rashmi Kumari","doi":"10.4269/ajtmh.25-0320","DOIUrl":"10.4269/ajtmh.25-0320","url":null,"abstract":"<p><p>Melioidosis is a potentially fatal infection caused by Burkholderia pseudomallei that is often underdiagnosed because of its diverse clinical presentations. We report the case of a 49-year-old female farmer from Tamil Nadu who presented with a 10-day history of fever, productive cough, and breathlessness followed by a rapidly progressive ulceronecrotic lesion on the forehead for 6 days. Examination revealed a 3 × 2 cm crusted eschar with surrounding edema. Blood, pus swab, and tissue bit grew B. pseudomallei, and imaging showed multiple abscesses in the lungs, liver, spleen, and brain. She was newly diagnosed with diabetes (hemoglobin A1c: 9.2%) and treated with intravenous meropenem, but she succumbed to refractory septic shock. This case highlights the need to recognize atypical cutaneous signs as early indicators of disseminated melioidosis, especially in endemic regions, and the importance of timely, appropriate antibiotic therapy.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"734-736"},"PeriodicalIF":1.6,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12493133/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144833764","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 Retrospective Analysis of Bacterial Infections (2021-2024) in a Reference Laboratory in Kathmandu, Nepal.","authors":"Sohani Bajracharya, Ajaya Basnet, Ranjan Bhele Shrestha, Jeevan Adhikari","doi":"10.4269/ajtmh.25-0116","DOIUrl":"10.4269/ajtmh.25-0116","url":null,"abstract":"<p><p>Of all the recognized public health threats, antimicrobial resistance (AMR) is among the most serious. Antimicrobial resistance may have a higher prevalence in low- and middle-income countries, where antimicrobial misuse is compounded by inadequate infection control measures. In this study, we examined AMR trends in bacterial infections in a reference laboratory in Kathmandu, Nepal, from 2021 to 2024. We collected the clinical records of infected patients, including demographic details, pathogen profiles, and antibiograms, from the electronic laboratory information system and analyzed them using SPSS version 17.0 (IBM Corp., Armonk, NY). Among 3,720 patients, 703 (19.7%; median age: 40 years; 395 [54.0%] female) had infections primarily caused by bacteria (91.7%; 723/731), followed by yeast (3.8%; 28/731). Urinary tract infections (55.9%; 290/703) were the most common. The predominant pathogen was Escherichia coli (41.3%; 290/703). Resistance rates in Enterobacterales, nonfermenters, and Gram-positive cocci were 31.0%, 43.4%, and 13.5%, respectively, for aminoglycosides; 49.7%, 42.8%, and 40.2%, respectively, for fluoroquinolones; 64.9%, 59.0%, and 65.6%, respectively, for cephalosporins; 47.3%, 77.4%, and 27.2%, respectively, for trimethoprim-sulfamethoxazole; and 83.0%, 100.0%, and 85.0%, respectively, for penicillins. Extensively drug-resistant (XDR; 19.1%; 134/703) and multidrug-resistant (29.2%; 205/703) bacteria exhibited >90% resistance to ciprofloxacin, erythromycin, and beta-lactams. Over time (2022-2024), resistance increased for aminoglycosides (27.7-32.3%), fluoroquinolones (43.5-54.1%), and penicillin with beta-lactamase inhibitors (PwBLIs; 35.9-58.7%) but decreased for cephalosporins (67.5-62.8%), carbapenems (23.3-18.7%), penicillins (85.2-82.1%), trimethoprim-sulfamethoxazole (59.6-42.2%), and nitrofurantoin (39.0-3.7%). A low rate of bacterial infections was detected among hospital visitors. Urinary tract infections were the most prevalent type of infection. Multidrug-resistant bacteria predominated over XDR bacteria. Resistance to beta-lactams declined over time; however, resistance to aminoglycosides, fluoroquinolones, and PwBLIs increased.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"749-757"},"PeriodicalIF":1.6,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12493258/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144798000","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":"Polymerase Chain Reaction-Based Diagnosis of Leishmaniasis Targeting Kinetoplast Minicircle DNA in Infants with Hemophagocytic Lymphohistiocytosis.","authors":"Heng Zhao, Shulan Shi, Ying Zhang, Haijing Shi, Guorun Jiang, Lilian Yang, Heng Li, Huiwen Zheng, Li Yu, Yun Liao, Xin Zhao, Mei Yuan, Na Li, Longding Liu, Dandan Li","doi":"10.4269/ajtmh.24-0792","DOIUrl":"10.4269/ajtmh.24-0792","url":null,"abstract":"<p><p>In this study, we aimed to assess the efficacy of polymerase chain reaction (PCR) targeting Leishmania kinetoplast minicircle DNA (kDNA) for diagnosing visceral leishmaniasis-associated hemophagocytic lymphohistiocytosis (VL-HLH). Three pediatric patients diagnosed with VL-HLH via the microscopic examination of bone marrow smears were selected to explore the diagnostic value of kDNA PCR in Leishmania species identification and parasite load quantification in three cases of visceral leishmaniasis. Total DNA was extracted from the bone marrow samples, and PCR testing targeting the Leishmania kDNA was conducted. The amplified PCR products were sequenced and analyzed by using National Center for Biotechnology Information Basic Local Alignment Search Tool for Leishmania species identification and homology cluster analysis. Furthermore, universal primers and probes were designed to quantify the kDNA load in patient samples through real-time quantitative PCR (qPCR) testing. Polymerase chain reaction testing targeting the kDNA gene yielded a specific 139 base pairs band in all samples. Real-time qPCR testing targeting the kDNA gene revealed significant amplification in all patients. The kDNA copy numbers for the three patients were 3,830/µL, 150/µL, and 77,168/µL, respectively. Homology analysis revealed 97.8% similarity between Patients 1 and 2, as well as 87.1% and 87.8% similarity between Patients 1 and 3 and Patients 2 and 3, respectively. All sequences were identified as belonging to the genus Leishmania, with Patients 1 and 2 clustering with Leishmania donovani sequences and Patient 3 clustering with Leishmania infantum. Polymerase chain reaction testing targeting the kDNA gene is a rapid, accurate, and sensitive method for detecting and quantifying Leishmania in VL-HLH patients. It also facilitates species identification through sequencing, demonstrating its potential as a valuable tool in clinical diagnostics.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"799-805"},"PeriodicalIF":1.6,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12493245/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144798003","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":"Eastern Equine Encephalitis Virus Exhibits More Charged Amino Acids in Its Envelope Proteins, Compared to Madariaga Virus.","authors":"Gladys Medina, Jose Luis Zambrano, Carmen Luisa Loureiro, Domingo J Garzaro, Miguel Barrios, Rosa Alba Salas, Scott C Weaver, Flor H Pujol","doi":"10.4269/ajtmh.24-0693","DOIUrl":"10.4269/ajtmh.24-0693","url":null,"abstract":"<p><p>Given the importance of eastern equine encephalitis virus (EEEV; complex lineage I) in veterinary and public health in North America, there is limited knowledge about lineages II, III, and IV, also known as Madariaga virus (MADV), which are prevalent in Central and South America. Because charge mutations in the envelope glycoproteins are critical to the emergence of Venezuelan equine encephalitis virus, we analyzed the structural polyproteins of Venezuelan MADV isolates and compared them with sequences of EEEV. Four substitutions involving positively charged residues were identified in the E3 (R44Q) and E2 (R205H/Q, K260T/A, and R310Q) proteins. Additionally, histidine residues were present in EEEV and absent in MADV: E2 (H82Y, H94Y, H114Q, and H181S) and E1 (H118Q). None of these amino acids were predicted to be under selective pressure or associated with a significant conformational change in the envelope proteins. However, some of these substitutions might still be associated with the virulence and pathogenicity of EEEV.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"879-882"},"PeriodicalIF":1.6,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12493260/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144798002","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":"The Impact and Sustainability of Multisector Interventions to Improve Water Quality and Food Safety in Complex Environments: A Cluster-Randomized Controlled Trial in Northern Uganda.","authors":"Ian G Moore, Yanlin Ren, Stacy Griswold, Carolyn Van Sant, Camille Heylen, Edgar Agaba, Regina Brown, Saurabh Mehta, Balaji Srinivasan, Gloria Desire Kayo, Troshbert Mwesigire, Marta Domini, Jacqueline Namusalisi, Daniele Lantagne, Merry Fitzpatrick, Anastasia Marshak, Marlene Hebie, Hugo De Groote, Patrick Webb, Shibani Ghosh","doi":"10.4269/ajtmh.24-0825","DOIUrl":"10.4269/ajtmh.24-0825","url":null,"abstract":"<p><p>In complex environments characterized as protracted humanitarian settings where public services are largely lacking, food and water contamination are significant contributors to malnutrition. Multisector, multilevel, community-driven programs may address these issues simultaneously and synergistically. A 1:1:1 cluster randomized controlled design was used to evaluate the effectiveness of two social and behavior change interventions in northern Uganda aimed at enabling participants to assess and act on key drivers of malnutrition: a core nutrition impact and positive practice (NIPP) intervention versus an NIPP+ intervention, which included additional nudges toward adopting improved technologies, compared with a control arm (NCT04209569). Primary outcomes included concentrations of Escherichia coli (E. coli) and total coliform in household water (baseline n = 359), total maize aflatoxins (parts per billion; baseline n = 271), and women's serum aflatoxin B1-lysine (nanograms (ng)/mL and picograms (pg)/mg albumin, baseline n = 452). Data were collected at three time points: baseline (pre-intervention), endline (post-intervention), and sustainability (1 year post-intervention). The NIPP+ intervention, but not the NIPP intervention, significantly reduced the risk of household E. coli water contamination at endline (RR = 0.76; 95% CI = 0.59-0.97), but this effect was not sustained. No significant intervention effects on maize aflatoxins or serum aflatoxin B1 were found. These findings highlight the need to examine factors that prevent sustained water quality gains, including structural barriers to behavior change and innovation adoption. Additionally, intervention groups may not have received sufficient exposure to market vendors, leading to less adoption of new technologies. Future interventions may benefit from improved program implementation and strengthened market connections for obtaining technologies and selling agricultural products.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"888-902"},"PeriodicalIF":1.6,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12493142/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144798004","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":"Chagas and Vector-Borne Disease Exposures in an Indigenous Community in the Ecuadorian Amazon: A Retrospective Study.","authors":"Rojelio Mejia, Bin Zhan, Nestor L Uzcategui, Andrea Lopez, Philip Cooper, Natalia Romero-Sandoval","doi":"10.4269/ajtmh.25-0200","DOIUrl":"10.4269/ajtmh.25-0200","url":null,"abstract":"<p><p>There are limited data on vector-borne diseases from the Ecuadorian Amazon, particularly among marginalized Indigenous populations. From a survey of Shuar communities in Ecuador, we measured IgG antibodies to Trypanosoma cruzi, dengue virus, and Leishmania spp. The prevalence of IgG antibodies was 7.4% for T. cruzi, 21.3% for dengue, and 96.8% for Leishmania spp. There was an increase in the risk of dengue infections with increasing age (per year; adjusted odds ratio [adj. OR]: 1.03, 95% CI: 1.01-1.05, P = 0.001) and among females (adj. OR: 2.17, 95% CI: 1.03-4.57, P = 0.041). There was an increase in T. cruzi anti-Tc24 IgG antibody levels with greater age (Spearman r = 0.553, P = 0.05). This study showed a high prevalence or exposure to Chagas disease, dengue, and Leishmania spp. There remains an unmet need for surveillance to monitor the transmission of Chagas and other vector-borne diseases and their associated morbidity in marginalized communities in the Ecuadorian Amazon.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"806-808"},"PeriodicalIF":1.6,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12493185/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144798001","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":"Coinfection with Respiratory Pathogens and Dengue Disease Severity in Puerto Rico, 2012-2024.","authors":"Matthew J Lozier, Diego M Canabal López, Brenda Torres-Velásquez, Zachary J Madewell, Olga Lorenzi, Aidsa Rivera, Janice Perez-Padilla, Laura E Adams, Yajaira Guzmán, Jorge Muñoz-Jordan, Tyler M Sharp, Luisa Alvarado-Domenech, Gabriela Paz-Bailey","doi":"10.4269/ajtmh.24-0744","DOIUrl":"10.4269/ajtmh.24-0744","url":null,"abstract":"<p><p>Differentiating between acute febrile illnesses (AFIs) caused by arboviruses like dengue virus (DENV) and other pathogens is challenging, particularly in the case of coinfections, which often require comprehensive diagnostic testing for accurate identification. Recognizing DENV coinfections is important because they may contribute to increased disease severity, and their identification can aid in patient management decisions. Using data from the Sentinel Enhanced Dengue Surveillance System in Puerto Rico (2012-2024), we compared patients with DENV monoinfection to those coinfected with DENV and another pathogen. All pathogens were identified via nucleic acid detection by using real-time, reverse transcriptase-polymerase chain reaction or serology. We examined demographic and clinical features linked to coinfection using Mann-Whitney-Wilcoxon, χ2, or Fisher's exact tests. Among 50,189 participants tested for DENV, 1,218 (2.4%) had DENV infections, with 1,172 (96.2%) monoinfections and 46 (3.8%) coinfections. The most frequent coinfecting pathogens were adenovirus (17.4%), influenza A (15.2%), human metapneumovirus (15.2%), and respiratory syncytial virus (10.9%). Dengue virus coinfections were associated with younger age (median: 13 versus 16 years; P = 0.011) and symptoms of rhinorrhea (52.2% versus 27.3%; P <0.001) and cough (60.9% versus 36.4%; P = 0.001). Among 549 hospitalized dengue patients, 20 (3.6%) had coinfections. Five of seven participants with DENV/influenza A coinfection were hospitalized. Hospitalization, intensive care unit admission, the administration of blood products, and severe dengue indicators (plasma leakage, severe bleeding, and organ involvement) were not significantly associated with DENV coinfection. Overall, DENV coinfections were uncommon in AFI cases in Puerto Rico, and they primarily involved respiratory viruses. Overlapping symptoms may complicate clinical management, emphasizing the importance of comprehensive pathogen testing in settings where arboviruses and respiratory viruses cocirculate.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"870-878"},"PeriodicalIF":1.6,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12493232/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144788064","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":"Probable Irukandji-Like Syndrome in the US Florida Keys.","authors":"Niki Viradia, Jesica Miroslava Godinez Paredes, Michael Kron","doi":"10.4269/ajtmh.25-0217","DOIUrl":"10.4269/ajtmh.25-0217","url":null,"abstract":"<p><p>Sixteen of the world's 50 known species of box jellyfish are associated with Irukandji syndrome, which involves a multitude of delayed reactionary and potentially life-threatening symptoms. The most common species associated with Irukandji syndrome is Carukia barnesi (C. barnesi), a very small member of the Carybdeid family. These box jellyfish are native to Australian waters, where most cases of Irukandji syndrome occur. However, cases of Irukandji-like syndrome have been reported worldwide after envenomation by species other than C. barnesi, including non-Carybdeid jellyfish. Herein, we report a probable new case of Irukandji-like syndrome in the US Florida Keys, a region where C. barnesi has not been recorded. Although it is unclear exactly which jellyfish are the causal organisms, a clustering of four incidents in the western Florida Keys suggests that jellyfish other than C. barnesi, or possibly non-Carybdeid jellyfish, are causing Irukandji-like syndromes in this area.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"917-918"},"PeriodicalIF":1.6,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12493255/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144788068","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":"Dengue Outbreaks and Antibody Seroprevalence in Buenos Aires.","authors":"Alejandro Macchia, Daniel Ferrante, Cristián Biscayart, Patricia Angeleri, María Belén Bouzas, Lilia Mammana, Fernán González Bernaldo de Quirós","doi":"10.4269/ajtmh.25-0148","DOIUrl":"10.4269/ajtmh.25-0148","url":null,"abstract":"<p><p>Buenos Aires, Argentina, a city with 3.1 million inhabitants, had a minimal prevalence of dengue until 2022, with nearly 25,000 cumulative reported cases. However, consecutive outbreaks in 2023 and 2024 significantly altered the epidemiological landscape, raising concerns about increasing viral circulation and a potential shift from a low-incidence, seasonal pattern toward more sustained transmission in this major urban setting. To assess the aftermath of the largest recorded dengue epidemic in Buenos Aires, we conducted a probabilistic, stratified, multistage serosurvey during the inter-epidemic period from August to October 2024. The study population consisted of 2.4 million adults, and dengue IgG and IgM antibodies were detected using a rapid immunoassay with an enzyme-linked fluorescence assay confirmation. Weighted seroprevalence reached 18.6% (95% CI: 15.6-21.5%) in 2024 (446,735 subjects). This represents a substantial increase in population immunity compared with previous estimates, likely reflecting the exceptional magnitude of the recent epidemic. The highest seropositivity rate was observed in informal settlements (38.1%), as well as in central (20.3%) and southern districts (21.3%), suggesting an uneven distribution of transmission risks. To the best of our knowledge, no previous seroprevalence studies in Argentina have directly assessed population immunity in the aftermath of a large-scale dengue outbreak, making this research particularly relevant. Our findings highlight a rapid shift in dengue virus circulation, underscoring the increasing vulnerability of Buenos Aires to dengue transmission. This surge in seroprevalence signals the need for strengthened vector control, improved surveillance, and targeted public health interventions, particularly in disadvantaged urban areas.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"865-869"},"PeriodicalIF":1.6,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12493259/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144788067","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":"Current Epidemiological Trends and Public Health Challenges of Hepatitis A Virus Infection in Thailand.","authors":"Yong Poovorawan, Sitthichai Kanokudom, Phattharaporn Inma, Pornjarim Nilyanimit, Nasamon Wanlapakorn","doi":"10.4269/ajtmh.25-0083","DOIUrl":"10.4269/ajtmh.25-0083","url":null,"abstract":"<p><p>Hepatitis A virus (HAV) remains a global public health concern, particularly in areas with poor sanitation. Thailand, once hyperendemic, has experienced a significant decline in HAV prevalence over the past five decades because of socioeconomic progress and improved public health measures. The median age of seroprevalence has increased, reflecting a shift to low endemicity. Notably, the most recent 2024 study reveals that the epidemiological pattern of hepatitis A in Thailand now corresponds to a low endemicity classification. Although HAV outbreaks were common from 1984 to 2014, recent cases are largely confined to high-risk groups, such as men who have sex with men and immigrants. However, low HAV vaccination coverage persists because of high costs and exclusion from the Expanded Program on Immunization. Addressing these gaps through improved vaccine access and cost-effectiveness analysis is crucial. This review examines Thailand's changing HAV epidemiology, the impact of public health interventions, and the need for enhanced vaccination strategies to sustain low prevalence, prevent outbreaks, and curb cross-border transmission.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":"724-727"},"PeriodicalIF":1.6,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12493123/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144788065","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}