Pub Date : 2025-12-01DOI: 10.1016/j.actatropica.2025.107910
Shimaa E Mohammed , Hend M Hussein , Noha A Elleboudy , Mariam I Ibrahim , Asmaa M Ammar
Cerebral schistosomiasis is a severe complication of chronic Schistosoma mansoni infection, yet the temporal relationship between parasitic burden and central nervous system pathology remains incompletely understood. This study investigated the temporal dynamics of worm burden and corresponding histopathological changes in experimental murine CNS schistosomiasis from 7 to 23 weeks post-infection. Adult worm counts (male, female, copula, and total) were determined at nine time points (weeks 7–23 post-infection) using hepatic portal perfusion. Histopathological evaluation of brain sections was performed using hematoxylin and eosin staining with a semi-quantitative scoring system (0–3). Total worm burden fluctuated significantly over time (H = 19.78, p = 0.011), peaking at week 11 (8.0 [7–9] worms). Histopathological scores exhibited a biphasic pattern: an acute inflammatory phase (weeks 7–13) with increasing gliosis and mononuclear infiltration, peaking at week 13 (score = 2.5), followed by a chronic phase (weeks 17–23) marked by vascular damage, neuronal degeneration, and fibrosis (score = 3.0 at week 17). Total worm burden correlated strongly with histopathological severity (rs = 0.724, p < 0.001), with the strongest associations observed during weeks 9–15. Murine cerebral schistosomiasis follows a predictable biphasic progression, with peak worm burden preceding maximal neuropathological damage. The mid-infection period (weeks 9–15) may represent a critical therapeutic window for intervention. These findings provide quantitative evidence for timing treatment strategies to mitigate CNS damage.
{"title":"Temporal evolution of neuropathological changes in the brain of Schistosoma mansoni-infected mice: A histopathological study","authors":"Shimaa E Mohammed , Hend M Hussein , Noha A Elleboudy , Mariam I Ibrahim , Asmaa M Ammar","doi":"10.1016/j.actatropica.2025.107910","DOIUrl":"10.1016/j.actatropica.2025.107910","url":null,"abstract":"<div><div>Cerebral schistosomiasis is a severe complication of chronic <em>Schistosoma mansoni</em> infection, yet the temporal relationship between parasitic burden and central nervous system pathology remains incompletely understood. This study investigated the temporal dynamics of worm burden and corresponding histopathological changes in experimental murine CNS schistosomiasis from 7 to 23 weeks post-infection. Adult worm counts (male, female, copula, and total) were determined at nine time points (weeks 7–23 post-infection) using hepatic portal perfusion. Histopathological evaluation of brain sections was performed using hematoxylin and eosin staining with a semi-quantitative scoring system (0–3). Total worm burden fluctuated significantly over time (H = 19.78, <em>p</em> = 0.011), peaking at week 11 (8.0 [7–9] worms). Histopathological scores exhibited a biphasic pattern: an acute inflammatory phase (weeks 7–13) with increasing gliosis and mononuclear infiltration, peaking at week 13 (score = 2.5), followed by a chronic phase (weeks 17–23) marked by vascular damage, neuronal degeneration, and fibrosis (score = 3.0 at week 17). Total worm burden correlated strongly with histopathological severity (r<sub>s</sub> = 0.724, <em>p</em> < 0.001), with the strongest associations observed during weeks 9–15. Murine cerebral schistosomiasis follows a predictable biphasic progression, with peak worm burden preceding maximal neuropathological damage. The mid-infection period (weeks 9–15) may represent a critical therapeutic window for intervention. These findings provide quantitative evidence for timing treatment strategies to mitigate CNS damage.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"272 ","pages":"Article 107910"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145530362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01DOI: 10.1016/j.actatropica.2025.107921
Jorge Jesús Rodríguez-Rojas , Edith Araceli Fernández-Figueroa , Pilar de Jesús Salas-Rodríguez , Josué Severo Ortiz-Barrera , Herón Huerta , Mario Octavio González-Reyes , Rosa María Sánchez-Casas , Ildefonso Fernández-Salas , Gabriel Gutiérrez-Granados , Ángel Rodríguez-Moreno
The primary transmission of Trypanosoma cruzi, causative agent of Chagas disease, to humans and animals is through the feces and urine of Triatominae. Therefore, knowledge of their ecology and distribution is crucial for establishing effective surveillance programs with citizen participation. This is coupled with geographic distribution models to predict the risk of transmission in the areas most affected by Chagas disease. Therefore, this study aims to: a) document and validate citizen participation on the iNaturalist in the collection and observation of triatomines, as well as exploring risk factors; b) detect natural T. cruzi infection in triatomines using molecular and parasitological methods; c) to review the historical and recent literature of Triatoma gerstaeckeri (Stål 1859) in Mexico, and d) develop current and potential distribution models of T. gerstaeckeri to infer risk zones for parasite transmission in Mexico. Data of T. gerstaeckeri were collected from three sources: iNaturalist (n = 87), fieldwork data (n = 68), and scientific articles and theses (n = 882). iNaturalist observations were validated from photographs, specimen capture, and distribution overlap. The prevalence of natural infection by T. cruzi was 21.73 % (5/23) in T. gerstaeckeri from Nuevo Leon, with DTU strains TcI and TcIII, the first reports of DTU in the state. Citizen participation data like iNaturalist can potentially document the presence of triatomines at broad spatial scales. Still, they also represent an opportunity to engage and educate the public in the surveillance and control of these insect vectors associated with Chagas disease.
{"title":"Citizen science to complement the surveillance of Triatominae (Hemiptera: Reduviidae) with data of Trypanosoma cruzi (Kinetoplastea: Trypanosomatidae) infection and spatial distribution models in northeast Mexico","authors":"Jorge Jesús Rodríguez-Rojas , Edith Araceli Fernández-Figueroa , Pilar de Jesús Salas-Rodríguez , Josué Severo Ortiz-Barrera , Herón Huerta , Mario Octavio González-Reyes , Rosa María Sánchez-Casas , Ildefonso Fernández-Salas , Gabriel Gutiérrez-Granados , Ángel Rodríguez-Moreno","doi":"10.1016/j.actatropica.2025.107921","DOIUrl":"10.1016/j.actatropica.2025.107921","url":null,"abstract":"<div><div>The primary transmission of <em>Trypanosoma cruzi</em>, causative agent of Chagas disease, to humans and animals is through the feces and urine of Triatominae. Therefore, knowledge of their ecology and distribution is crucial for establishing effective surveillance programs with citizen participation. This is coupled with geographic distribution models to predict the risk of transmission in the areas most affected by Chagas disease. Therefore, this study aims to: a) document and validate citizen participation on the iNaturalist in the collection and observation of triatomines, as well as exploring risk factors; b) detect natural <em>T. cruzi</em> infection in triatomines using molecular and parasitological methods; c) to review the historical and recent literature of <em>Triatoma gerstaeckeri</em> (Stål 1859) in Mexico, and d) develop current and potential distribution models of <em>T. gerstaeckeri</em> to infer risk zones for parasite transmission in Mexico. Data of <em>T. gerstaeckeri</em> were collected from three sources: iNaturalist (<em>n</em> = 87), fieldwork data (<em>n</em> = 68), and scientific articles and theses (<em>n</em> = 882). iNaturalist observations were validated from photographs, specimen capture, and distribution overlap. The prevalence of natural infection by <em>T. cruzi</em> was 21.73 % (5/23) in <em>T. gerstaeckeri</em> from Nuevo Leon, with DTU strains TcI and TcIII, the first reports of DTU in the state. Citizen participation data like iNaturalist can potentially document the presence of triatomines at broad spatial scales. Still, they also represent an opportunity to engage and educate the public in the surveillance and control of these insect vectors associated with Chagas disease.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"272 ","pages":"Article 107921"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145562384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01DOI: 10.1016/j.actatropica.2025.107919
Willy Ramos , Alfredo Enrique Oyola-García , Aída Aguirre Gonzáles , Jhony A. De La Cruz-Vargas , Miguel Luna , Tania Alarcón , Mónica Meléndez , Juan Huaccho-Rojas , Yudy Cley Cóndor-Rojas
Background
This study analyzed the time of dengue-related deaths in two regions of Peru during the atmospheric phenomena of El Niño Costero and Cyclone Yaku, which caused the largest dengue epidemic ever registered in Peru at that time.
Methods
We included 40 dengue-related deaths between January 1 and June 3, 2023. A death was considered to be dengue-related if it occurred as a consequence of the clinical signs or the clinical evolution of dengue during the medical care process, or in which dengue significantly contributed to the clinical worsening of another disease. We reviewed the research database of the deaths as well as the clinical epidemiology records, death certificates, and laboratory test results. A time analysis was performed from the date of onset of symptoms, the date of the first visit to a health establishment, the date the dengue diagnosis was first registered, and the date of death.
Results
The median age of death was 51 years, 51.2% had at least one comorbidity, and 14% had self-medicated. The median times from symptom onset to first consultation, diagnosis and from diagnosis to death were 3, 0, and 1 day, respectively. Adults presented a time from symptom onset to first consultation that was significantly greater than that of the other age groups (p = 0.048). The diagnosis time was significantly less than that seen at regional government (GORE) public establishments compared to private establishments (p = 0.014) and greater in pediatrics (p = 0.018). The time from diagnosis until death was significantly less in those who self-medicated (p = 0.041).
Conclusion
Several factors significantly influenced time from symptom onset to first consultation, diagnosis time, and diagnosis-to-death time in dengue-related deaths during the FENC epidemic and Cyclone Yaku in 2023. These factors should be analyzed to reduce mortality in Peru during future climate-related epidemics.
{"title":"Time analysis of dengue-related deaths that occurred in two regions of Peru during the climatic-atmospheric phenomena El Niño Costero and Cyclone Yaku","authors":"Willy Ramos , Alfredo Enrique Oyola-García , Aída Aguirre Gonzáles , Jhony A. De La Cruz-Vargas , Miguel Luna , Tania Alarcón , Mónica Meléndez , Juan Huaccho-Rojas , Yudy Cley Cóndor-Rojas","doi":"10.1016/j.actatropica.2025.107919","DOIUrl":"10.1016/j.actatropica.2025.107919","url":null,"abstract":"<div><h3>Background</h3><div>This study analyzed the time of dengue-related deaths in two regions of Peru during the atmospheric phenomena of El Niño Costero and Cyclone Yaku, which caused the largest dengue epidemic ever registered in Peru at that time.</div></div><div><h3>Methods</h3><div>We included 40 dengue-related deaths between January 1 and June 3, 2023. A death was considered to be dengue-related if it occurred as a consequence of the clinical signs or the clinical evolution of dengue during the medical care process, or in which dengue significantly contributed to the clinical worsening of another disease. We reviewed the research database of the deaths as well as the clinical epidemiology records, death certificates, and laboratory test results. A time analysis was performed from the date of onset of symptoms, the date of the first visit to a health establishment, the date the dengue diagnosis was first registered, and the date of death.</div></div><div><h3>Results</h3><div>The median age of death was 51 years, 51.2% had at least one comorbidity, and 14% had self-medicated. The median times from symptom onset to first consultation, diagnosis and from diagnosis to death were 3, 0, and 1 day, respectively. Adults presented a time from symptom onset to first consultation that was significantly greater than that of the other age groups (<em>p</em> = 0.048). The diagnosis time was significantly less than that seen at regional government (GORE) public establishments compared to private establishments (<em>p</em> = 0.014) and greater in pediatrics (<em>p</em> = 0.018). The time from diagnosis until death was significantly less in those who self-medicated (<em>p</em> = 0.041).</div></div><div><h3>Conclusion</h3><div>Several factors significantly influenced time from symptom onset to first consultation, diagnosis time, and diagnosis-to-death time in dengue-related deaths during the FENC epidemic and Cyclone Yaku in 2023. These factors should be analyzed to reduce mortality in Peru during future climate-related epidemics.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"272 ","pages":"Article 107919"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145556042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01DOI: 10.1016/j.actatropica.2025.107920
Amanda Andrade do Rosário , Laura Posada-Lopez , Marília Fonseca Rocha , Guilherme Loureiro Werneck , Fredy Galvis-Ovallos
Visceral leishmaniasis is a zoonosis of high epidemiological relevance, caused by protozoan parasites of the Leishmaniinae subfamily, mainly of the Leishmania genus and transmitted by hematophagous phlebotomine sand flies. Vector-borne disease control faces significant challenges, and innovative strategies towards the vector – such as the use of the endosymbiont bacteria Wolbachia – have gained prominence for their ability to manipulate the reproduction of their hosts and modulate their immunity, reducing pathogen transmission. However, little is known about natural Wolbachia infection in the sand fly population. This study aimed to assess the circulation of Wolbachia in sand flies from Montes Claros, a visceral leishmaniasis-endemic area in Minas Gerais, Brazil. A total of 1.191 females Lutzomyia longipalpis were analyzed, and Wolbachia DNA was detected in 30 samples (2.5%), with a homogeneous presence among the points sampled. DNA sequences revealed a single strain, wPup, that has not been previously described in sand flies. The positive Wolbachia samples were also tested for Leishmania spp, however, no DNA was detected.
{"title":"Natural occurrence of Wolbachia in Phlebotominae (Diptera: Psychodidae) in Montes Claros, Minas Gerais - Brazil","authors":"Amanda Andrade do Rosário , Laura Posada-Lopez , Marília Fonseca Rocha , Guilherme Loureiro Werneck , Fredy Galvis-Ovallos","doi":"10.1016/j.actatropica.2025.107920","DOIUrl":"10.1016/j.actatropica.2025.107920","url":null,"abstract":"<div><div>Visceral leishmaniasis is a zoonosis of high epidemiological relevance, caused by protozoan parasites of the Leishmaniinae subfamily, mainly of the <em>Leishmania</em> genus and transmitted by hematophagous phlebotomine sand flies. Vector-borne disease control faces significant challenges, and innovative strategies towards the vector – such as the use of the endosymbiont bacteria <em>Wolbachia</em> – have gained prominence for their ability to manipulate the reproduction of their hosts and modulate their immunity, reducing pathogen transmission. However, little is known about natural <em>Wolbachia</em> infection in the sand fly population. This study aimed to assess the circulation of <em>Wolbachia</em> in sand flies from Montes Claros, a visceral leishmaniasis-endemic area in Minas Gerais, Brazil. A total of 1.191 females <em>Lutzomyia longipalpis</em> were analyzed, and <em>Wolbachia</em> DNA was detected in 30 samples (2.5%), with a homogeneous presence among the points sampled. DNA sequences revealed a single strain, <em>w</em>Pup, that has not been previously described in sand flies. The positive <em>Wolbachia</em> samples were also tested for <em>Leishmania</em> spp, however, no DNA was detected.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"272 ","pages":"Article 107920"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145562369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01DOI: 10.1016/j.actatropica.2025.107936
Shyam Sundar Sah
{"title":"Comment on “When microbiology is missing: A prospective observational study on empirical first-line antibiotic treatment (FLAT) in Ethiopia”","authors":"Shyam Sundar Sah","doi":"10.1016/j.actatropica.2025.107936","DOIUrl":"10.1016/j.actatropica.2025.107936","url":null,"abstract":"","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"272 ","pages":"Article 107936"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145706884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01DOI: 10.1016/j.actatropica.2025.107930
Arineia Soares Silva , Rejane Lima Leda , Wilsandrei Cella , Victor Irungu Mwangi , Rosa Amélia Gonçalves Santana , Alexandre Vilhena Silva-Neto , Maria de Nazaré Paula da Silva , Rogério Santos Pereira , Stefanie Costa Pinto Lopes , Gisely Cardoso Melo , Paulo Filemon Paolucci Pimenta , Fernando Fonseca Almeida-Val , Adalberto Luis Val , Djane Clarys Baía-da-Silva , Wuelton Marcelo Monteiro
Anopheles aquasalis mosquito, a key Plasmodium vivax vector in coastal Latin America, can be sensitive to environmental shifts. This study assessed the impact of IPCC AR5-projected climate scenarios on mosquito survival, infectivity, and immunity. Four scenarios were simulated in digitally controlled climate rooms: a forest-based environmental control and three IPCC projections - (i) Scenario RCP 4.5 (light, +1.0°C and +250 ppm CO2 on current scenario); RCP Scenario 6.0 (intermediate, +2.5°C and +400 ppm CO2 over current scenario) and RCP Scenario 8.5 (extreme, +4.5°C and +850 ppm CO2 over current scenario). Female An. aquasalis mosquitoes were infected with P. vivax via artificial membrane feeding, and survival, infection, and expression of immune genes (Attacin, Cecropin, and Defensin) evaluated. All conditions supported parasite development, with no significant differences in infection rates (54 - 68 %) or oocyst intensity. However, mosquito survival declined significantly under RCPs 6.0 and 8.5, with probabilities of 18.6 % and 6.5 % by day 7 post-infection respectively, versus 40 % in the non-blood-fed controls (p<0.001). Attacin expression differed significantly between the experimental control and RCP 4.5 (P = 0.0379), and RCP 8.5 (P = 0.0016); RCPs 6.0 and 8.5 (P = 0.0210). Defensin also varied between RCP 4.5 and 6.0 (P = 0.0359); RCP 6.0 and experimental control (P = 0.0464), and RCP 8.5 and experimental control (P = 0.0274), suggesting decreased immune activation under higher heat and CO₂ stress. Cecropin showed no significant variations. While An. aquasalis retained infectivity under all simulated conditions, the increased mortality and altered immune gene expression observed in RCPs 6.0 and 8.5 suggest that future climatic stress may compromise vector fitness.
{"title":"Predicted future climate scenarios impact survival and immune response but not Plasmodium vivax infection in Anopheles aquasalis (Diptera, Culicidae), the primary vector of coastal Central and South America and the Caribbean Islands","authors":"Arineia Soares Silva , Rejane Lima Leda , Wilsandrei Cella , Victor Irungu Mwangi , Rosa Amélia Gonçalves Santana , Alexandre Vilhena Silva-Neto , Maria de Nazaré Paula da Silva , Rogério Santos Pereira , Stefanie Costa Pinto Lopes , Gisely Cardoso Melo , Paulo Filemon Paolucci Pimenta , Fernando Fonseca Almeida-Val , Adalberto Luis Val , Djane Clarys Baía-da-Silva , Wuelton Marcelo Monteiro","doi":"10.1016/j.actatropica.2025.107930","DOIUrl":"10.1016/j.actatropica.2025.107930","url":null,"abstract":"<div><div><em>Anopheles aquasalis</em> mosquito, a key <em>Plasmodium vivax</em> vector in coastal Latin America, can be sensitive to environmental shifts. This study assessed the impact of IPCC AR5-projected climate scenarios on mosquito survival, infectivity, and immunity. Four scenarios were simulated in digitally controlled climate rooms: a forest-based environmental control and three IPCC projections - (i) Scenario RCP 4.5 (light, +1.0°C and +250 ppm CO2 on current scenario); RCP Scenario 6.0 (intermediate, +2.5°C and +400 ppm CO2 over current scenario) and RCP Scenario 8.5 (extreme, +4.5°C and +850 ppm CO2 over current scenario). Female <em>An. aquasalis</em> mosquitoes were infected with <em>P. vivax</em> via artificial membrane feeding, and survival, infection, and expression of immune genes (<em>Attacin, Cecropin, and Defensin</em>) evaluated. All conditions supported parasite development, with no significant differences in infection rates (54 - 68 %) or oocyst intensity. However, mosquito survival declined significantly under RCPs 6.0 and 8.5, with probabilities of 18.6 % and 6.5 % by day 7 post-infection respectively, versus 40 % in the non-blood-fed controls (p<0.001). <em>Attacin</em> expression differed significantly between the experimental control and RCP 4.5 (P = 0.0379), and RCP 8.5 (P = 0.0016); RCPs 6.0 and 8.5 (P = 0.0210). <em>Defensin</em> also varied between RCP 4.5 and 6.0 (P = 0.0359); RCP 6.0 and experimental control (P = 0.0464), and RCP 8.5 and experimental control (P = 0.0274), suggesting decreased immune activation under higher heat and CO₂ stress. <em>Cecropin</em> showed no significant variations. While <em>An. aquasalis</em> retained infectivity under all simulated conditions, the increased mortality and altered immune gene expression observed in RCPs 6.0 and 8.5 suggest that future climatic stress may compromise vector fitness.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"272 ","pages":"Article 107930"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145676207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01DOI: 10.1016/j.actatropica.2025.107928
Berihun Mulu Yayeh , Kevin Fong-Rey Liu
Abstract
Background
Trachoma, caused by Chlamydia trachomatis, remains the leading infectious cause of preventable blindness globally, with children aged 1–9 years bearing the highest burden. Ethiopia continues to report a high prevalence despite ongoing control efforts. The Health Extension Program (HEP) aims to improve household hygiene and sanitation. This is the first study to quantify the direct association between household-level HEP adherence and active trachoma prevalence.
Objective
To assess the prevalence of active trachoma among children aged 1–9 years and examine its association with household-level HEP adherence in Northern Ethiopia.
Methods
A community-based cross-sectional study was conducted among 422 children in Wag Hemra Zone, Northern Ethiopia from March–May 2025. A simple random sampling identified households, and one child per household was included. Data on socio-demographics, HEP adherence, and WASH practices were collected using structured questionnaires. Clinical examination for active trachoma (TF/TI) was performed by trained ophthalmic nurses following the WHO simplified grading system. Binary and multivariable logistic regression analyses identified factors associated with active trachoma (p < 0.05).
Results
The overall prevalence of active trachoma was 6.3% (95% CI: 4.0–9.2%). Only 40% of households demonstrated high HEP adherence (≥75% of recommended practices). In multivariable analysis, children from low-adherence households were more likely to have active trachoma (AOR = 3.2; 95% CI: 1.5–6.7). Poor facial hygiene (AOR = 2.8; 95% CI: 1.3–5.9) and lack of functional latrines (AOR = 2.5; 95% CI: 1.1–5.6) were also significant predictors. Age, sex, and parental education were not independently associated.
Conclusion
Despite improvements in HEP coverage, active trachoma remains above the WHO elimination threshold in Northern Ethiopia. Household-level adherence to hygiene and sanitation practices, facial cleanliness, and latrine use are key determinants of disease risk. Strengthening HEP implementation, promoting facial hygiene, and improving sanitation infrastructure are critical for accelerating progress toward trachoma elimination. These findings underscore the need for enhanced community-level interventions and targeted HEP strategies to accelerate trachoma elimination in Ethiopia and similar endemic settings.
{"title":"Household health extension program adherence and risk of active trachoma in children aged 1–9 years: Evidence from Northern Ethiopia","authors":"Berihun Mulu Yayeh , Kevin Fong-Rey Liu","doi":"10.1016/j.actatropica.2025.107928","DOIUrl":"10.1016/j.actatropica.2025.107928","url":null,"abstract":"<div><div>Abstract</div></div><div><h3>Background</h3><div>Trachoma, caused by <em>Chlamydia trachomatis</em>, remains the leading infectious cause of preventable blindness globally, with children aged 1–9 years bearing the highest burden. Ethiopia continues to report a high prevalence despite ongoing control efforts. The Health Extension Program (HEP) aims to improve household hygiene and sanitation. This is the first study to quantify the direct association between household-level HEP adherence and active trachoma prevalence.</div></div><div><h3>Objective</h3><div>To assess the prevalence of active trachoma among children aged 1–9 years and examine its association with household-level HEP adherence in Northern Ethiopia.</div></div><div><h3>Methods</h3><div>A community-based cross-sectional study was conducted among 422 children in Wag Hemra Zone, Northern Ethiopia from March–May 2025. A simple random sampling identified households, and one child per household was included. Data on socio-demographics, HEP adherence, and WASH practices were collected using structured questionnaires. Clinical examination for active trachoma (TF/TI) was performed by trained ophthalmic nurses following the WHO simplified grading system. Binary and multivariable logistic regression analyses identified factors associated with active trachoma (p < 0.05).</div></div><div><h3>Results</h3><div>The overall prevalence of active trachoma was 6.3% (95% CI: 4.0–9.2%). Only 40% of households demonstrated high HEP adherence (≥75% of recommended practices). In multivariable analysis, children from low-adherence households were more likely to have active trachoma (AOR = 3.2; 95% CI: 1.5–6.7). Poor facial hygiene (AOR = 2.8; 95% CI: 1.3–5.9) and lack of functional latrines (AOR = 2.5; 95% CI: 1.1–5.6) were also significant predictors. Age, sex, and parental education were not independently associated.</div></div><div><h3>Conclusion</h3><div>Despite improvements in HEP coverage, active trachoma remains above the WHO elimination threshold in Northern Ethiopia. Household-level adherence to hygiene and sanitation practices, facial cleanliness, and latrine use are key determinants of disease risk. Strengthening HEP implementation, promoting facial hygiene, and improving sanitation infrastructure are critical for accelerating progress toward trachoma elimination. These findings underscore the need for enhanced community-level interventions and targeted HEP strategies to accelerate trachoma elimination in Ethiopia and similar endemic settings.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"272 ","pages":"Article 107928"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145653150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01DOI: 10.1016/j.actatropica.2025.107924
Leonardo França do Nascimento , Isabela Caroline Oliveira da Silva , Eliseu Baldez Neto , Beatriz Elise de Andrade-Silva , Nayara Yoshie Sano , Eduardo José Lopes-Torres , Filipe Martins Santos
Rodents and didelphids are highly diverse and abundant groups that can be found in different ecological niches, including anthropized environments. This can favor a high diversity of zoonotic agents, constituting a complex network of ecological interactions. Nematode parasites can have adaptative flexibility to emerge as new diseases, considering its ecology and diversity, so we aimed to evaluate the functional role of a network interaction between small mammals and nematodes parasites. We used a literature search to construct our network. A total of 52 articles were selected for analysis, from which 80 records of nematodes parasitizing small mammals were retrieved, being 24 species associated with Didelphimorphia and 56 with Rodentia. No nematode species were found parasitizing hosts from both orders. The network exhibited significant modularity (QW = 0.62, P = 0.01), but did not show significant overall specialization (H2 = 0.48, P = 0.23), nor nestedness (WNODF metric = 0.03, P = 0.1), but there is a nestedness patterns both within modules (WNODASM = 0.17, P = 0.02) and across the entire network (WNODA = 0.03, P = 0.01). We observed 18 modules all related to the host family. All the hosts roles were classified as either ultraperipheral (81.58 %) or peripheral (18.42 %); and the nematodes were 90 % classified as ultraperipheral, 7.5 % classified as peripheral. Only Aspidodera raillieti and Guerrerostrongylus zetta were classified as provincial hubs. This could highlight the importance of niche sharing by hosts in the cycle transmission of those parasites and how the loss of these key species could result in module fragmentation and compromise system stability, emphasizing their critical role in network architecture and in hotspots of biodiversity and threaten biomes such as Atlantic Forest and Pantanal.
啮齿动物和双栖动物是高度多样化和丰富的群体，可以在不同的生态位中找到，包括人类环境。这有利于人畜共患病原体的高度多样性，构成一个复杂的生态相互作用网络。考虑到线虫寄生虫的生态学和多样性，它可能具有适应性灵活性，从而出现新的疾病，因此我们旨在评估小型哺乳动物与线虫寄生虫之间网络相互作用的功能作用。我们使用文献检索来构建我们的网络。选取52篇文献进行分析，共检索到80条寄生小兽类的线虫记录，其中与双翅虫相关的线虫24种，与啮齿目相关的线虫56种。没有发现寄生于这两个目的线虫种类。该网络表现出显著的模块化（QW = 0.62, P = 0.01），但不表现出显著的整体专业化（H2 = 0.48, P = 0.23）和嵌套性（WNODF度量= 0.03,P = 0.1），但在模块内（WNODASM = 0.17, P = 0.02）和整个网络（WNODA = 0.03, P = 0.01）都存在嵌套性模式。我们观察到18个模块都与寄宿家庭有关。所有的主机角色被归类为超外围（81.58%）或外围（18.42%）；超外周线虫占90%，外周线虫占7.5%。只有铁路蛛形线虫和泽塔格雷罗圆线虫被列为省级枢纽。这可以突出宿主生态位共享在这些寄生虫循环传播中的重要性，以及这些关键物种的丧失如何导致模块破碎和损害系统稳定性，强调它们在网络架构和生物多样性热点中的关键作用，并威胁到大西洋森林和潘塔纳尔等生物群落。
{"title":"Host–parasite interaction networks between nematodes and non-volant small mammals in Brazil: A systematic review and ecological network analysis","authors":"Leonardo França do Nascimento , Isabela Caroline Oliveira da Silva , Eliseu Baldez Neto , Beatriz Elise de Andrade-Silva , Nayara Yoshie Sano , Eduardo José Lopes-Torres , Filipe Martins Santos","doi":"10.1016/j.actatropica.2025.107924","DOIUrl":"10.1016/j.actatropica.2025.107924","url":null,"abstract":"<div><div>Rodents and didelphids are highly diverse and abundant groups that can be found in different ecological niches, including anthropized environments. This can favor a high diversity of zoonotic agents, constituting a complex network of ecological interactions. Nematode parasites can have adaptative flexibility to emerge as new diseases, considering its ecology and diversity, so we aimed to evaluate the functional role of a network interaction between small mammals and nematodes parasites. We used a literature search to construct our network. A total of 52 articles were selected for analysis, from which 80 records of nematodes parasitizing small mammals were retrieved, being 24 species associated with Didelphimorphia and 56 with Rodentia. No nematode species were found parasitizing hosts from both orders. The network exhibited significant modularity (Q<sub>W</sub> = 0.62, <em>P</em> = 0.01), but did not show significant overall specialization (H2 = 0.48, <em>P</em> = 0.23), nor nestedness (WNODF metric = 0.03, <em>P</em> = 0.1), but there is a nestedness patterns both within modules (WNODA<sub>SM</sub> = 0.17, <em>P</em> = 0.02) and across the entire network (WNODA = 0.03, <em>P</em> = 0.01). We observed 18 modules all related to the host family. All the hosts roles were classified as either ultraperipheral (81.58 %) or peripheral (18.42 %); and the nematodes were 90 % classified as ultraperipheral, 7.5 % classified as peripheral. Only <em>Aspidodera raillieti</em> and <em>Guerrerostrongylus zetta</em> were classified as provincial hubs. This could highlight the importance of niche sharing by hosts in the cycle transmission of those parasites and how the loss of these key species could result in module fragmentation and compromise system stability, emphasizing their critical role in network architecture and in hotspots of biodiversity and threaten biomes such as Atlantic Forest and Pantanal.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"272 ","pages":"Article 107924"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145621291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-01DOI: 10.1016/j.actatropica.2025.107932
Yuke Zeng , Asmaa M.I. Abuzeid , Qin Meng , Shuyu Chen , Xiaoruo Tan , Cuiqin Huang , Shiquan Lu , Teng Zhong , Yuanpeng Hu , Yisong Liu , Wei Liu
Protein post-translational modifications (PTMs) refer to the covalent attachment of chemical groups to polypeptide chains after protein synthesis, which expands protein chemical diversity and enhances functional versatility. Common PTM types include phosphorylation, glycosylation, and lysine acetylation (Kac), a major, reversible PTM regulated by lysine acetyltransferases (KATs) and lysine deacetylases (KDACs). Kac cross-regulates with other modifications to govern chromatin transcription and epigenetic programs, and occurs in histones, nucleoproteins, and cytoplasmic regulatory factors. In this study, we employed proteomic approaches to investigate lysine acetylation in proteins derived from snake-borne spargana for the first time. A total of 390 acetylated proteins and 655 Kac sites were identified. Subcellular localization analysis revealed these acetylated proteins were predominantly localized in the cytoplasm, followed by the mitochondria, nucleus, extracellular matrix, and plasma membrane. This study aims to expand our understanding of protein acetylation in Spirometra mansoni plerocercoid larvae and provide valuable information for designing effective drugs or vaccines to control sparganosis.
{"title":"Lysine acetylation in the spargana of Spirometra mansoni: Insights into glycolysis and EF-hand domain proteins","authors":"Yuke Zeng , Asmaa M.I. Abuzeid , Qin Meng , Shuyu Chen , Xiaoruo Tan , Cuiqin Huang , Shiquan Lu , Teng Zhong , Yuanpeng Hu , Yisong Liu , Wei Liu","doi":"10.1016/j.actatropica.2025.107932","DOIUrl":"10.1016/j.actatropica.2025.107932","url":null,"abstract":"<div><div>Protein post-translational modifications (PTMs) refer to the covalent attachment of chemical groups to polypeptide chains after protein synthesis, which expands protein chemical diversity and enhances functional versatility. Common PTM types include phosphorylation, glycosylation, and lysine acetylation (Kac), a major, reversible PTM regulated by lysine acetyltransferases (KATs) and lysine deacetylases (KDACs). Kac cross-regulates with other modifications to govern chromatin transcription and epigenetic programs, and occurs in histones, nucleoproteins, and cytoplasmic regulatory factors. In this study, we employed proteomic approaches to investigate lysine acetylation in proteins derived from snake-borne spargana for the first time. A total of 390 acetylated proteins and 655 Kac sites were identified. Subcellular localization analysis revealed these acetylated proteins were predominantly localized in the cytoplasm, followed by the mitochondria, nucleus, extracellular matrix, and plasma membrane. This study aims to expand our understanding of protein acetylation in <em>Spirometra mansoni</em> plerocercoid larvae and provide valuable information for designing effective drugs or vaccines to control sparganosis.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"272 ","pages":"Article 107932"},"PeriodicalIF":2.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145666405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-19DOI: 10.1016/j.actatropica.2025.107911
Fathelrhman El Guma
Visceral leishmaniasis (VL) is a climate-driven disease with a complex epidemiological pattern and is difficult to predict, especially in regions like eastern Sudan, where disease patterns vary substantially from season to season. In this study, our objective was to forecast the monthly incidence of VL in Gedaref State based on key climatic drivers—precipitation, temperature, and humidity. To capture the complex dynamics of disease transmission, we propose a new hybrid model based on wavelet transforms and state-of-the-art deep learning models to decompose multi-scale patterns and learn linear and nonlinear relationships.. We developed and tested hybrid models: Wavelet-Gaussian Process Regression (Wavelet-GPR), Wavelet–Spatiotemporal Graph Neural Network (Wavelet–StemGNN), and Wavelet–Temporal Convolutional Network with Bidirectional LSTM (Wavelet–TCN–BiLSTM). These were compared against a traditional Vector Autoregressive model (VAR) as a baseline. We employed a fixed temporal split (2000–2018 for training; 2019–2022 for testing). All models were implemented using Python and their performance was evaluated using key forecasting metrics: RMSE, MAE, , and MAPE.
Our wavelet-GPR model outperformed both baseline and other deep learning methods in terms of prediction accuracy (RMSE = 43.93, MAE = 32.85, = 0.93, MAPE = 14.6%), with the smallest prediction errors and well-calibrated 95% predictive intervals. The results of our study underscore the possibility of improving the disease surveillance and early warning systems by means of hybrid wavelet-based artificial intelligence models, particularly in resource constraints situations. The projection may be employed for monthly early warning bulletins and the strategic pre-positioning of diagnostics and medicines in Gedaref. The method is straightforward to modify to different VL locations in Sudan and East Africa, and it requires much re-calibration. Future projects will include more layers of environmental and socio-economic data to make predictions and planning operations easier.
{"title":"Forecasting visceral leishmaniasis in Sudan using hybrid wavelet based deep learning models on climate driven multivariate time series","authors":"Fathelrhman El Guma","doi":"10.1016/j.actatropica.2025.107911","DOIUrl":"10.1016/j.actatropica.2025.107911","url":null,"abstract":"<div><div>Visceral leishmaniasis (VL) is a climate-driven disease with a complex epidemiological pattern and is difficult to predict, especially in regions like eastern Sudan, where disease patterns vary substantially from season to season. In this study, our objective was to forecast the monthly incidence of VL in Gedaref State based on key climatic drivers—precipitation, temperature, and humidity. To capture the complex dynamics of disease transmission, we propose a new hybrid model based on wavelet transforms and state-of-the-art deep learning models to decompose multi-scale patterns and learn linear and nonlinear relationships.. We developed and tested hybrid models: <em>Wavelet-Gaussian Process Regression (Wavelet-GPR)</em>, Wavelet–Spatiotemporal Graph Neural Network (Wavelet–StemGNN), and Wavelet–Temporal Convolutional Network with Bidirectional LSTM (Wavelet–TCN–BiLSTM). These were compared against a traditional Vector Autoregressive model (VAR) as a baseline. We employed a fixed temporal split (2000–2018 for training; 2019–2022 for testing). All models were implemented using Python and their performance was evaluated using key forecasting metrics: RMSE, MAE, <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span>, and MAPE.</div><div>Our wavelet-GPR model outperformed both baseline and other deep learning methods in terms of prediction accuracy (RMSE = 43.93, MAE = 32.85, <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> = 0.93, MAPE = 14.6%), with the smallest prediction errors and well-calibrated 95% predictive intervals. The results of our study underscore the possibility of improving the disease surveillance and early warning systems by means of hybrid wavelet-based artificial intelligence models, particularly in resource constraints situations. The projection may be employed for monthly early warning bulletins and the strategic pre-positioning of diagnostics and medicines in Gedaref. The method is straightforward to modify to different VL locations in Sudan and East Africa, and it requires much re-calibration. Future projects will include more layers of environmental and socio-economic data to make predictions and planning operations easier.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"272 ","pages":"Article 107911"},"PeriodicalIF":2.5,"publicationDate":"2025-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145562323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号