American Journal of Tropical Medicine and Hygiene最新文献

{"title":"Digitally Integrated Disease Management System in Rwanda: Community Healthcare Worker Perspectives.","authors":"Jean Claude Semuto Ngabonziza, Nouh Saad Mohamed, Marie Fidele Muremba, Hervé Rutebuka, Sylvere Mugumya, Manasseh Wandera Gihana, Ayman Ahmed","doi":"10.4269/ajtmh.26-0053","DOIUrl":"10.4269/ajtmh.26-0053","url":null,"abstract":"<p><p>As digital health tools are increasingly deployed to support community-based primary healthcare, understanding frontline user experiences is critical for effective implementation and scale-up. Here, community health workers' (CHWs) perspectives on the digitally integrated disease management system (d-IDS) in Rwanda are discussed. The d-IDS intervention was intended to improve the cost-effectiveness of community-based screening, patient management, and disease surveillance through a mobile digital platform. Before implementation, user acceptance testing and cascade training prepared CHWs, their supervisors, and health facility staff. During implementation, continuous supervision and qualitative assessments of the system were conducted. Qualitative data were collected through focus group discussions and semi-structured key informant interviews. The CHWs widely appreciated the system's ease of use, comprehensiveness, availability in Kinyarwanda (local language), offline functionality, improved data management, and ability to expedite effective patient management cascades compared with paper-based registers. Home-based screening reduced patient time and costs of care and enhanced equity and access to care, bringing Rwanda closer to achieving Universal Healthcare Coverage. However, challenges included increased workload, inadequate or lack of incentives, internet connectivity constraints, system rigidity in updating household records, and initially low digital literacy among some CHWs. Ongoing digitalization initiatives will inform national scale-up and policy choices.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615288/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149036137","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":"Pulmonary Dirofilaria immitis Infection and Concurrent Pleural Lymphangiomatosis in a Young Woman from Costa Rica: A Diagnostic Challenge after 20 Years of Silence.","authors":"Daniel Cascante-Serrano, Manuel Villalobos-Zúñiga, Daniela Salazar-Porras, Cristian Campos, Alberto Solano-Barquero, Javier Mora, Alicia Rojas","doi":"10.4269/ajtmh.26-0392","DOIUrl":"10.4269/ajtmh.26-0392","url":null,"abstract":"<p><p>Human dirofilariasis is an underreported, vector-borne disease caused by the filarioid Dirofilaria immitis. A case of pulmonary dirofilariasis is reported in a woman from Costa Rica, manifesting respiratory distress, marked eosinophilia of 47%, and severe chylothorax. Pleural biopsies revealed a lymphoplasmacytic reaction with eosinophils, and bronchoalveolar fluid analysis revealed 28S and internal transcribed spacer 1 fragments that were 100% and 99.3% similar to D. immitis, respectively, and a coxA sequence identical to Wolbachia from D. immitis. Other infectious, autoimmune, and malignant causes were excluded through an extensive diagnostic workup. Initial treatment included methylprednisolone, albendazole, and a subsequent course of albendazole plus doxycycline; however, the chylothorax recurred. A biopsy of the left upper lobe confirmed a pleural lymphangiomatosis. The patient was discharged with continued treatment but was clinically stable. This case reveals the diagnostic complexity of filariasis and underlying lymphadenopathies coexisting in endemic regions and highlights the value of an integrated clinical, molecular, and histopathological approach.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615286/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149036096","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":"Neither, Nor.","authors":"B Jason Brotherton","doi":"10.4269/ajtmh.26-0436","DOIUrl":"10.4269/ajtmh.26-0436","url":null,"abstract":"","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615261/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149036074","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":"Absence of Plasmodium falciparum Histidine-Rich Protein 2 and 3 (Pfhrp2/3) Gene Deletions in Rizal, Palawan, the Philippines.","authors":"Jennifer S Luchavez, Alison Paolo N Bareng, Freya Spencer, Samuel G Thorburn, Maria Lourdes M Macalinao, Fe Esperanza J Espino, Chris J Drakeley, Julius Clemence R Hafalla, Lynn Grignard","doi":"10.4269/ajtmh.25-0616","DOIUrl":"10.4269/ajtmh.25-0616","url":null,"abstract":"<p><p>Microscopy and rapid diagnostic tests (RDTs) are used in the Philippines as the gold standard for malaria diagnosis. However, parasites evading RDT detection have recently emerged in other settings as a result of deletions in Plasmodium falciparum histidine-rich protein genes (pfhrp2 and pfhrp3). Failure to detect and treat individuals carrying these deletions may result in increased malaria transmission and hinder elimination efforts. In addition to the implications for malaria elimination efforts, we emphasize that false-negative RDT results caused by pfhrp2/3 deletions pose a critical risk to patient outcomes, as individuals with active P. falciparum infections may go untreated. Sixty-three samples collected from Palawan, the Philippines, were interrogated for the presence of Plasmodium isolates and pfhrp deletions. All 63 samples were microscopically positive for P. falciparum. Although only 27 (43%) were positive for RDTs, all samples were confirmed free of pfhrp2 and pfhrp3 deletions by nested polymerase chain reaction (PCR) tests. RDT false negatives in the study were most likely caused by low parasite densities. Incorporating molecular monitoring of histidine-rich protein 2 deletions into routine malaria surveillance would improve assessments of the performance of the current RDTs and help strengthen strategies toward malaria elimination by 2030.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615282/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149023677","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":"Infant Scrub Typhus: A 10-Year Experience from a Tertiary Center in South India (The ScrubIn Study).","authors":"Rahul D'Souza, Baker Ninan Fenn, Anish Sam George, Urmi Ghosh, Jolly Chandran, Winsley Rose","doi":"10.4269/ajtmh.25-0632","DOIUrl":"10.4269/ajtmh.25-0632","url":null,"abstract":"<p><p>Scrub typhus is a potentially fatal and neglected tropical infectious disease caused by the bacterium Orientia tsutsugamushi; limited information is available on scrub typhus in infants. In the present retrospective study, the clinical presentation, laboratory findings, and outcomes of infants with scrub typhus admitted to a tertiary care hospital in India were investigated over a decade. A retrospective review of 49 infants (<1 year) with laboratory-confirmed scrub typhus admitted between 2014 and 2023 was conducted. Clinical, laboratory, and outcome data were analyzed to identify predictors of severe disease. A total of 49 infants, with a mean age of 5 months, were diagnosed with scrub typhus. Most cases clustered between October and January, indicating seasonality of the infection. Despite their limited indoor exposure, nearly half of the infants had an identifiable eschar, predominantly on the head or neck and in the inguinal region. Severe disease, defined by organ dysfunction (acute respiratory distress syndrome, shock, myocarditis, encephalitis, renal failure, or hepatic failure), was observed in 24 (49.0%) infants, all of whom required pediatric intensive care unit care. Elevated leukocyte count, severe thrombocytopenia, and elevated hepatic transaminases predicted severity, whereas the presence of an eschar was protective. The overall mortality was 10.2%, which was considerably higher than the 1% to 3% reported in broader pediatric cohorts, underscoring infants as a uniquely vulnerable group. This was one of the largest infant scrub typhus cohorts, highlighting distinctive epidemiological and clinical features, possible transmission pathways, susceptibility, outcomes, and early markers of severity, underscoring the need for heightened clinical suspicion and timely doxycycline therapy in endemic regions.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615262/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149023669","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":"Comparison of Methods for Assessing Chlamydia trachomatis Transmission Intensity: A Systematic Review.","authors":"Kristen K Renneker, Che-Chi Lin, Jennifer L Hsieh, Pamela J Hooper, Robert Butcher, T Déirdre Hollingsworth, Diana L Martin, Anthony W Solomon, Emma M Harding-Esch","doi":"10.4269/ajtmh.25-0541","DOIUrl":"10.4269/ajtmh.25-0541","url":null,"abstract":"<p><p>Field-graded trachomatous inflammation-follicular (TF) has limitations as the sole indicator of Chlamydia trachomatis (Ct) transmission for trachoma programmatic decision-making. To assess the relationship between field-graded TF and other methodologies for evaluating Ct transmission intensity, a systematic review was conducted. A total of 35,764 studies were screened, yielding 235 included studies from 49 countries spanning the years of data collection from 1991 to 2021 and the years of publication from 1991 to 2022. The relationship between TF and other indicators was stronger before mass drug administration (MDA) versus after MDA initiation: TF versus infection (R2 = 0.43, P = 0.004 versus R2 = 0.05, P = 0.140, respectively), TF versus seroprevalence (R2 = 0.55, P <0.001 versus R2 = 0.09, P = 0.084, respectively), and TF versus seroconversion rate (SCR; R2 = 0.52, P = 0.012 versus R2 = 0.26, P = 0.061, respectively). Post-MDA initiation, infection and SCR were highly correlated (R2 = 0.71, P = 0.001). These results are strongly suggestive of the poor performance of TF prevalence for guiding programmatic decision-making post-MDA initiation. Infection and/or serology should be considered in these settings.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615270/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149023642","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":"Uterine Cervical Tuberculosis Mimicking Malignancy: Case Series from Ethiopia.","authors":"Abdu Assen Ahmed, Bemnet Yazew Abegaz, Seid Getahun Abdela, Silamlak Sisay Abegaz, Fekadu Hailemariam Getaneh","doi":"10.4269/ajtmh.25-0752","DOIUrl":"10.4269/ajtmh.25-0752","url":null,"abstract":"<p><p>Uterine cervical tuberculosis is a rare manifestation of female genital tuberculosis, accounting for 2.4% of female genital tract tuberculosis cases. Although genitourinary tuberculosis is a common form of extrapulmonary tuberculosis, it most frequently affects the kidneys, bladder, ureters, and fallopian tubes, with cervical involvement being uncommon and often underdiagnosed because of its nonspecific presentation. Three women aged 29, 33, and 40 years from Ethiopia with histologically confirmed cervical tuberculosis who presented with odorless whitish vaginal discharge, pelvic pain, and abnormal uterine bleeding are reported in the present study. All were initially clinically suspected of having cervical cancer because of abnormal cervical findings and abnormal discharge. However, histopathological examination confirmed isolated cervical tuberculosis without systemic involvement. All patients achieved complete clinical resolution after a 6-month course of first-line anti-tuberculosis therapy. These cases highlight the importance of considering cervical tuberculosis in the differential diagnosis of cervical lesions in tuberculosis-endemic settings.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615283/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149023598","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 Chronic, Solitary Skin Ulcer Owing to Sporotrichosis.","authors":"Nicolas Antunez de Mayolo, Ciro Maguiña-Vargas, Omayra Chincha","doi":"10.4269/ajtmh.26-0146","DOIUrl":"10.4269/ajtmh.26-0146","url":null,"abstract":"","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615285/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149023679","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":"Investigation of Dinga Dinga: A Cluster of Bilateral Lower-Extremity Tremors-Bundibugyo District, Uganda, 2023-2024.","authors":"Sophia Mulei, Daniel Orit, Mary J Choi, Shannon Whitmer, Katrin S Sadigh, Jimmy Baluku, Kami Smith, Alison Todres, Calvin R Torach, Benigna Namara, Michael Nanjubu, Simon P Lubega, Abdullah Baguma, Emmanuel Ejoku, Jens H Kuhn, Shuiqing Yu, Sandor Karpathy, Ariel Christiansen, Terry Fei Fan Ng, James Sejvar, Trevor Shoemaker, Joel M Montgomery, Julius Lutwama, Daniel Kadobera, Christopher Kiyita, Henry Mwebesa, Luke Nyakarahuka, Stephen Balinandi, John D Klena","doi":"10.4269/ajtmh.26-0088","DOIUrl":"10.4269/ajtmh.26-0088","url":null,"abstract":"<p><p>In September 2023, a cluster of unexplained illness in women affecting their ability to stand/walk was reported at Bundibugyo Hospital, Uganda. Field investigations were conducted to verify reports, conduct active case finding, and identify potential causes using a hypothesis-generating questionnaire, a neurological examination tool, and a standardized laboratory panel. As of January 31, 2025, 136 patients were identified; all were female. Among 108 with age data, the median age was 18 years old, and all but one lived in Bundibugyo District. All reported bilateral lower-extremity tremors interfering with their ability to stand/walk that resolved when sitting or lying down. Of 75 women evaluated, 33 (44%) were acutely symptomatic at assessment. Tremors lasted between 4 days and 3 months. Of 90 women who provided symptom recurrence information, 20 (22%) reported recurrent episodes. No shared environmental exposures of concern were identified among 76 patients with data. Although limited female-specific exposures were noted, no known toxins were identified among patients. Blood specimens were submitted for laboratory testing, and 24 of 93 (26%) tested positive for Plasmodium. One of 34 (3%) tested positive for Shigella spp. Three of 87 (3%) were positive for Ekpoma virus 2 (EKV2), and 41 of 80 (51%) were anti-EKV2 IgG positive. Metagenomic sequencing confirmed two of the EKV2 cases and identified rickettsiae-specific reads in one individual. It is still unknown whether the cause is an infectious agent or an environmental toxin. This outbreak highlights the importance of strong field epidemiology and laboratory capacity in investigating emerging neurological syndromes.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615289/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149023631","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":"Genetic Relatedness of Cambodian Plasmodium falciparum Isolates Was Associated with Geography and Occupation.","authors":"Emma Rowley, Bing Guo, Mariusz Wojnarski, Michele D Spring, Sabaithip Sriwichai, Brian A Vesely, Joana C Silva, Norman C Waters, Sasikanya Thaloengsok, Piyaporn Sai-Ngam, Chaiyaporn Chaisatit, Paphavee Lertsethtakarn, Somethy Sok, Prom Satharath, Sidhartha Chaudhury, Chanthap Lon, Dysoley Lek, David Saunders, Timothy D O'Connor, Shannon Takala-Harrison","doi":"10.4269/ajtmh.26-0091","DOIUrl":"10.4269/ajtmh.26-0091","url":null,"abstract":"<p><p>Cambodia is nearing Plasmodium falciparum (P. falciparum) elimination, but targeted interventions are needed to prevent resurgence. Identity-by-descent (IBD)-based methods offer insight into parasite relatedness and transmission dynamics. Pairwise genetic relatedness was estimated among 107 P. falciparum isolates collected from military personnel and farmers during two clinical trials in Cambodia from 2014 to 2016. Using existing whole-genome sequence data, IBD relatedness was estimated as the proportion of the genome shared IBD between isolates. Associations between relatedness and epidemiological factors, including occupation, location, time, age, and sex, were evaluated. Network-based clustering was used to identify highly related isolate groups and associated covariates. High mean IBD sharing (40%) suggested clonal expansion or low transmission; isolates from Oddar Meanchey Province shared >20% more of their genome IBD than Kratie Province isolates (P <2.2e-16). Within Oddar Meanchey, isolates from individuals with different occupations shared 7.2% less of their genome IBD than farmer pairs (probability of direction [pd] = 0.999), after adjusting for age. Highly related clusters (>90% IBD) were associated with occupation, K13 mutation (C580Y versus R539T), and P. falciparum chloroquine resistance transporter mutation (P = 0.0027, 0.0001, and 0.0001, respectively). Isolates from mixed-occupation pairs had lower odds of being highly related (>90% IBD) than farmer pairs (pd = 0.958). High overall IBD sharing may reflect elimination efforts and the expansion of drug-resistant lineages. Differences in between-province relatedness underscore how geography shapes relatedness patterns. Lower relatedness among mixed-occupation pairs compared with farmer pairs suggests occupation-associated exposure differences, with occupation potentially acting as a proxy for micro-epidemiological exposure factors such as location or behavior, highlighting the need for locally tailored interventions.</p>","PeriodicalId":7752,"journal":{"name":"American Journal of Tropical Medicine and Hygiene","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13615265/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149023658","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}