Introduction

Orally transmitted acute Chagas disease has emerged in Latin America as a severe outbreak-associated presentation characterized by high parasite inoculum, systemic inflammation, and frequent early cardiac involvement. However, longitudinal evidence describing clinical phenotypes, temporal progression, and predictors of early cardiac risk remains limited. This study aimed to characterize phenotype-defined trajectories and identify determinants of severe cardiac involvement in outbreak-associated acute Chagas disease in Colombia.

Methods

This longitudinal cohort study included 104 patients diagnosed with orally transmitted acute Trypanosoma cruzi infection between 2000 and 2023. Patients were classified into predefined clinical phenotypes based on systemic severity and cardiac involvement. Temporal intervals from symptom onset to diagnosis and treatment initiation were measured. Serial electrocardiography was performed during the acute phase and at approximately 6 and 12 months. Multivariable regression models evaluated predictors of severe cardiac phenotype and intensive care admission.

Results

Three phenotypes were identified: mild systemic (28%), inflammatory non-cardiac (29%), and severe cardiac (43%). Acute myocarditis occurred in 43% of patients and electrocardiographic abnormalities in 63%. The hospitalization rate reached 82% among severe cardiac cases, and intensive care admission occurred exclusively in this group (18%). Early mortality was 2.9%, confined to fulminant myocarditis. Diagnostic delay exceeding 10 days independently predicted severe cardiac phenotype (adjusted OR 2.4; 95% CI 1.1–5.3). At 12 months, electrocardiographic abnormalities were resolved in 67% of affected individuals, while 33% had persistent alterations, predominantly among severe cardiac phenotypes.

Conclusions

Orally transmitted acute Chagas disease follows distinct phenotype-defined trajectories with markedly different early cardiac risks and recovery patterns. Severe cardiac involvement identifies a high-risk clinical course. Early diagnosis and structured cardiac follow-up are essential to reduce morbidity in outbreak settings.

Introduction

Canine filarial parasites, including Dirofilaria immitis and Acanthocheilonema reconditum, can cause zoonotic infections in humans. Dirofilaria immitis and Acanthocheilonema reconditum, however, respond differently to drug treatments and, therefore, it is necessary to discriminate between these two parasites during diagnosis.

Methods

Light microscope blood surveys of canines were used to identify the presence of D. immitis and A. reconditum infections and co-infections in dogs that were life-long residents of Manaus (Amazonas, Brazil). The ITS-1 and 5S nuclear ribosomal DNA sequences and the mitochondrial CO1 and 12S gene sequences of filarial parasites were amplified by PCR and then Sanger sequenced for the molecular taxonomic classification of 20 individual microfilariae. These 20 individual microfilariae were isolated by laser dissection from a single canine blood sample, which morphological analysis of microfilariae suggested contained both D. immitis and A. reconditum parasites.

Results

A total of 20 individual microfilariae, which all morphologically appeared as Dirofilaria immitis, had two or more taxonomically informative PCR fragments amplified and Sanger sequenced. More than five ITS-1, 5S, 12S and CO1 DNA sequences were recovered from the twenty individual microfilariae. All recovered sequences showed 100% identity to database reference sequences matching A. reconditum.

Conclusions

Acanthocheilonema reconditum is present in the state of Amazonas and indeed the city of Manaus. Acanthocheilonema reconditum microfilariae are more difficult to distinguish from D. immitis than has previously been reported and it may, in fact, not be possible to reliably discriminate between these two species by the morphological features of their microfilariae alone. Although the possibility that A. reconditum and D. immitis form hybrids cannot be ruled out by this work, no evidence of hybrids or geneflow between these parasites was detected in our study.

Cryptosporidiosis is a significant public health concern in low-income countries, causing diarrhea-related morbidity and mortality. Cryptosporidium infection also affects livestock, leading to economic losses, with farm animals potentially serving as reservoirs for human transmission via contaminated food and water. Despite its importance, the epidemiology of cryptosporidiosis in Eastern Ethiopia remains poorly studied. A health facility and community based cross-sectional study was conducted between November 2022 and November 2023 in Dire Dawa Administration and Shinile, Eastern Ethiopia by including 756 children under five years of age with diarrhea, 184 community children, and 628 young livestock. Sociodemographic and other relevant variables were collected using a structured questionnaire and checklist. Fresh fecal specimens from children and livestock were collected, and initial stained by LED fluorescence microscopy, while remaining stool samples were stored at −20 °C for ELISA and molecular analyses. Stool samples tested positive by LED fluorescence microscopy and/or ELISA were processed by PCR targeting the small subunit ribosomal ribonucleic acid and glycoprotein 60 loci. Poisson regression with robust variance and Firth logistic regression were used to assess factors associated with Cryptosporidium infection. The prevalence of Cryptosporidium infection, as detected by LED-AP microscopy, was 15.2% among diarrheic children, 6.5% among community children, and 4.3% among young livestock. In children, C. hominis (64%) and C. parvum (36%) were identified, with gp60 subtype families Ia, Ib, and Id for C. hominis and IIe and IIc for C. parvum; the predominant subtypes were C. hominis IdA15 and C. parvum IIeA10G1. Among livestock, C. ubiquitum, C. xiaoi (subtype XXIIIg), and C. ryanae were detected. In children, Cryptosporidium infection was significantly associated with season, caregiver educational status, contact with diarrheic individuals, exclusive breastfeeding, handwashing after toileting, and use of toilet paper after defecation. In livestock, herd/flock size, source of drinking water for animal and animal caregiver age were significantly associated with Cryptosporidium infection.

Introduction: Schistosomiasis is reported to be one of the most important worm infestations of mankind and is widely distributed over three continents, affecting more than 200 million people. Mass administration of praziquantel has taken place in many centers focusing only on children attending public schools. The purpose of this study was to assess the impact of mass treatment with praziquantel among students of Tsangaya School (Almajiri Schools) in Kura Local Government, Kano State. Methods: The study is a cross-sectional prospective interventional study involving four Tsangaya Schools named Tsangaya A, Tsangaya B, Tsangaya C, and Tsangaya D, from which 181 Almajiri students were recruited and questionnaires administered. Urine and blood samples were collected before and after drug intervention for macroscopic and microscopic examination for detection of Schistosoma eggs and assessment of packed cell volume (PCV) for possible risk of anemia. Results: The majority of the Almajiri students (90.6%) were infected with Schistosoma haematobium only, while 1.7% were co-infected with S. mansoni, given the overall prevalence of 92.3%. Tsangaya A has the highest prevalence of 32.0%, while Tsangaya B has the lowest of 14.9%. Tsangaya C has a prevalence of 24.9%, while that of Tsangaya D has 20.4%. The prevalence dropped to 12.7% after intervention. The mean PCV (M=34.80%, SD=5.75) of the participant was found to be significantly lower than the PCV among participants after treatment (M=35.57%, SD=5.48), t=-4.923, df=166, P<0.001. The binary logistic regression model predicted a high (OR=2.65) risk of developing schistosomiasis when staying for a duration of more than 10 years. Conclusion: This study showed that urinary schistosomiasis was prevalent among students of Tsangaya schools and that praziquantel is effective. There is a need for health education in this community.

Introduction:
Acute Encephalitis Syndrome (AES) in India reflects complex interplay of factors at the agent–host–environment interface, involving Japanese Encephalitis (JE) and other zoonotic pathogens such as scrub typhus, West Nile virus, Leptospira etc. The interconnected risks underscore the critical need for a robust coordinated multisectoral approach.

This presentation examines how multisectoral collaboration contributed to the decline of AES/JE and how improved understanding of AES aetiology reshaped program strategies.

Methods:
A qualitative synthesis of national program interventions using a multisectoral collaborative implementation model. Methods included on-the-spot field visits by health workers, strengthened program-manager supervision, periodic reviews, and rigorous monitoring and evaluation. inputs were drawn from cross-sectoral partners—Health, Animal Husbandry, Rural Development, Education, Tribal Health, Panchayati Raj Institutions, national and international agencies like BMGF, PATH, medical colleges, and research agencies (ICMR, NIMHANS). Importantly, GHSA–CDC-supported laboratories and surveillance platforms significantly strengthened AES/JE diagnostic capacity and case confirmation.

Results:
Serological and molecular evidence identified scrub typhus as responsible for nearly half of AES cases, with dengue, malaria, and other pathogens contributing substantially. Only 10–15% were JE, challenging earlier assumptions. Targeted interventions for these etiologies, combined with JE vaccination, vector control, and improved diagnostics, led to substantial reductions in AES cases and deaths.

Coclusion:

The study highlights how evidence-driven governance and cross-sector coordination can transform policy, strengthen practice, and advance sustainable AES/JE control.

Introduction

Accurate diagnostics of dengue virus (DENV) infection are essential for patient management, outbreak control, and vaccine implementation. Serological testing plays a key role, especially when molecular assays are unavailable or viremia subsides; yet, cross-reactivity with other flaviviruses remains a challenge. This study examined the diagnostic accuracy of four Euroimmun ELISAs, including a newly developed dual-cut-off Anti-DENV IgG ELISA.

Methods

The Dengue Virus NS1 ELISA, Anti-Dengue Virus Type 1-4 ELISA (IgM), Anti-Dengue Virus Type 1-4 ELISA (IgG; native antigen/gE-based), and the novel Anti-Dengue Virus NS1 ELISA 2.0 (IgG; recombinant NS1-based, with an alternative higher cut-off for flavivirus-endemic regions) were analyzed. Sensitivity was determined using sera from 22 Vietnamese patients with RT-PCR-confirmed DENV infection, collected during acute (t1, 1-6dpo), early convalescent (t2, 4-9dpo), and late convalescent (t3, 13-19dpo) phases. Specificity was assessed with samples from 500 healthy German blood donors (HBD) and 40 patients each with West Nile virus (WNV) or Zika virus (ZIKV) infection, all serologically positive for the respective virus.

Results

Sensitivities were 90.5%/70.0%/0% (t1/t2/t3) for NS1, 33.3%/85.0%/77.3% for IgM, 66.7%/100%/100% for IgG, and 33.3%/65.0%/100% vs. 19.1%/50.0%/100% for IgG 2.0 (standard vs. alternative cut-off). Combined NS1/IgM testing achieved 100% sensitivity in single acute-phase samples. Overall specificity was 85.7% (HBD/WNV/ZIKV: 95.0%/50.0%/5.0%) for IgG, compared to 95.7% (98.2%/95.0%/65.0%) vs. 99.5% (99.8%/97.5%/97.5%) for IgG 2.0 (standard vs. alternative cut-off).

Conclusion

Euroimmun ELISAs support customized, highly accurate and versatile diagnostic strategies applicable to various dengue testing contexts. Combining NS1 and IgM ELISAs offers an alternative to molecular assays during the acute phase of infection. The native antigen/gE-based IgG ELISA enables early sensitive IgG detection, although with limited specificity. With minimal cross-reactivity, the NS1-based dual-cut-off ELISA 2.0 (IgG) reliably captures DENV-specific IgG dynamics and enhances differentiation from other flaviviruses, which could provide an advantage in the use for convalescent-phase diagnostics, surveillance, and pre-vaccination serostatus determination.

Introduction: Japanese encephalitis (JE) remains a major public health concern in India, particularly in rural and peri-urban regions where environmental conditions favor vector proliferation. The primary vectors, especially Culex species, are highly sensitive to climatic and land-use changes. Predicting future vector distribution under changing environmental scenarios is critical for proactive surveillance and disease prevention. This study proposes the use of a species distribution modeling approach to map the current and future distribution of Japanese encephalitis vectors in India and to estimate potential vector abundance and associated disease risk by 2030. Methods: Occurance records of confirmed JE mosquito vectors, including Culex tritaeniorhynchus, will be compiled from entomological surveys, literature reviews, and published databases across India. Environmental predictors such as temperature, precipitation, vegetation indices, elevation, and land-use variables will be incorporated. Species distribution models will be developed using MaxEnt, which applies a maximum entropy algorithm to estimate habitat suitability from presence-only data. Future projections for 2030 will be generated using climate scenarios derived from global climate models (GCMs). Habitat suitability outputs will be integrated with human population density and historical case data to model potential changes in vector abundance and projected JE risk. Results: The model is expected to indentify high-suitability zones in endemic states and predict geographic expansion or shifts in vector distribution by 2030. Areas with increasing climatic suitability may correspond to higher projected vector abundance and elevated JE transmission risk. Conclusion: MaxEnt-based predictive modeling offers a robust tool for forecasting JE vector distribution and future disease risk. Integrating ecological suitability with epidemiological data can support targeted vector control, vaccination planning, and early warning systems for Japanese encephalitis in India.

Malaria is one of the most prevalent infectious parasitic diseases worldwide, placing well over 216 million people at risk of infection. India contributes a substantial share of malaria cases in Southeast Asia, particularly in forested and tribal regions where ecological conditions favor vector breeding and transmission. Gadchiroli district in eastern Maharashtra is predominantly forest-covered and inhabited largely by tribal communities living near forest ecosystems, making it highly vulnerable to malaria transmission. Among the 12 blocks in the district, Korchi block is considered one of the most malaria-prone areas. The present study analyzed malaria surveillance data from two Primary Health Centers (PHCs), Kotgul and Botekasa, in the Korchi block to assess seasonal, demographic, parasitological, and spatial patterns of malaria incidence. A total of 443 cases were reported at Kotgul PHC and 130 cases at Botekasa PHC. Malaria incidence remained low during the pre-monsoon months (January–May) but increased sharply with the onset of the monsoon, peaking in July and declining gradually from August to December. Individuals aged ≥15 years accounted for the majority of cases, likely due to occupational exposure related to agriculture and forest activities. Plasmodium falciparum was the predominant parasite species. Spatial analysis revealed focal transmission with several hotspot villages contributing disproportionately to the disease burden. These findings highlight the importance of pre-monsoon vector control, strengthened surveillance, and hotspot-based interventions for effective malaria control.

Introduction

American tegumentary leishmaniasis (ATL) remains a major neglected tropical disease in Latin America. Brazil accounts for a substantial proportion of cases worldwide, with transmission strongly influenced by ecological and socioeconomic factors. Investigating temporal and demographic trends is essential to better understand the current epidemiological dynamics of the disease.

Methods

A nationwide ecological study was conducted using secondary data from the Brazilian Notifiable Diseases Information System (SINAN), available through the DATASUS platform. Confirmed ATL cases reported between 2007 and 2025 were analyzed. Variables included sex, age group, and region of residence. Descriptive epidemiological analyses were performed to evaluate demographic patterns and geographic distribution.

Results

Between 2007 and 2025, 351,267 confirmed ATL cases were reported in Brazil. A pronounced male predominance was observed (72.9% of cases), suggesting occupational or environmental exposure patterns. Adults aged 20–39 years represented the most affected group (38.9%), followed by individuals aged 40–59 years (25.1%), indicating higher incidence among economically active populations. Geographically, the North region concentrated the largest share of cases (43.5%), followed by the Northeast (28.4%), reflecting the persistence of endemic transmission in tropical and Amazonian areas.

Conclusions

The epidemiological profile of ATL in Brazil reveals strong demographic and geographic disparities, with higher incidence among adult males and populations living in northern tropical regions. These findings highlight the continued need for targeted surveillance and control strategies in endemic areas and reinforce the importance of strengthening public health interventions in high-transmission settings.

Introduction:

Antimicrobial resistance (AMR) is a critical global health challenge driven by inappropriate antibiotic use across human, animal, and environmental sectors (1,2). In livestock farming, irrational antibiotic practices and poor awareness contribute significantly to the emergence and spread of resistant pathogens (3,4). Strengthening antibiotic stewardship at the community level is essential within the One Health framework. This study aimed to assess gaps in knowledge, attitudes, and practices (KAP) related to antibiotic use among livestock farmers.

Methods:

A cross-sectional, questionnaire-based study was conducted among 30 livestock farmers in rural Karnataka. Data was collected using a structured, pre-validated KAP questionnaires covering domains of antibiotic awareness, AMR knowledge, usage practices and environmental factors. Responses were recorded in the local language and analyzed descriptively as proportions.

Results:

Although 70% of participants were aware of antibiotics, only 40% correctly identified their appropriate use for bacterial infections. Awareness of AMR was limited (30%), reflecting trends reported in similar settings (5). Inappropriate practices were prevalent, with over 60% of farmers reporting non-prescription antibiotic use and nearly half discontinuing treatment prematurely, undermining antibiotic stewardship (6). Knowledge gaps regarding withdrawal periods and antibiotic residues in animal products were significant. Environmental dimensions of AMR, including contamination of soil and water, were poorly recognized (7). Despite these gaps, a majority expressed positive attitudes toward improved practices and willingness to participate in stewardship training.

Conclusion:

Substantial gaps in antibiotic stewardship exist among livestock farmers, driven by inadequate knowledge and unsafe practices. Targeted interventions including farmer education, improved veterinary access, and regulatory enforcement are essential. Integrating these strategies into a One Health framework is crucial in mitigating AMR and promoting sustainable antibiotic use (3,8).