The American Journal of Tropical Medicine and Hygiene

This cross-sectional study assessed hygienic practices, microbial contamination, and associated factors among street food vendors in Mymensingh City, Bangladesh, from August 2024 to February 2025. Using purposive sampling, 300 vendors were evaluated through structured questionnaires, observational assessments, and laboratory analysis of food samples (n = 300) for bacterial load (log-transformed Total Viable Count, log_TVC). Results revealed that 87.33% (95% CI: 83.6-91.1) of vendors practiced poor hygiene: 90.7% (95% CI: 87.4-94.0) did not cover food, 7% (95% CI: 4.1-9.9) used disinfectants, and 81.00% (95% CI: 76.6-85.4) reused ingredients beyond one day. Knowledge gaps were stark, with 89.7% (95% CI: 86.3-93.1%) demonstrating insufficient basic hygiene knowledge and 90.7% (95% CI: 87.4-94.0%) lacking understanding of hygienic food processing. Education significantly influenced practices; secondary-educated vendors exhibited markedly better hygiene awareness (65.0% vs. 2.89% in uneducated groups). Bacterial loads varied across food types, with Velpuri showing the highest mean log_TVC (8.00, 95% CI: 7.65-8.35) and fast food the lowest (7.69, 95% CI: 7.34-8.03). Significant correlations emerged between hygiene knowledge and practices: vendors aware of foodborne diseases were more likely to use gloves (Spearman's r = 0.199, p = 0.001) and cover food (r = 0.118, p = 0.041). Challenges included financial constraints (62.25% [95% CI: 56.1-68.4] among uneducated vendors), knowledge gaps, and time limitations. The study underscores systemic issues in street food safety, driven by low education and economic barriers. Interventions targeting vendor education, affordable hygiene solutions, and stricter enforcement of ingredient freshness protocols are urgently needed to mitigate foodborne disease risks in urban Bangladesh.

Background: Dengue emerged as a new public health threat in the Rohingya refugee camps in Coxs Bazar, Bangladesh, in 2021 and expanded into large-scale upsurges in subsequent years. Evidence on dengue epidemiology and clinical presentation in protracted refugee settings remains limited, despite the need for stronger outbreak preparedness and case management in these contexts. Objectives: To describe the epidemiological, clinical, and diagnostic characteristics of the dengue upsurge among Rohingya refugees and surrounding host communities in Coxs Bazar, Bangladesh, and to identify predictors of inpatient admission and diagnostic positivity patterns. Methods: This retrospective observational study used anonymized surveillance data from the International Organization for Migration (IOM) dengue patient database. Rapid diagnostic test (RDT)-confirmed dengue cases identified across 36 IOM-supported health facilities in Ukhiya and Teknaf between 1 October 2021 and 31 December 2024 were included. Demographic, epidemiological, clinical, and laboratory variables were summarized using descriptive statistics. Weekly incidence was aggregated by epidemiological week and calendar year, and epidemic growth and decay phases were modelled using phase-specific Poisson regression. Multivariable logistic regression was used to identify predictors of inpatient admission and to examine associations between delay in presentation and RDT positivity patterns, adjusting for age and sex. Results: A total of 35,581 RDT-confirmed dengue cases were reported, of which 90.2% occurred among Rohingya refugees. The median age was 17 years (IQR 7-30), and 46.0% of cases were among children aged 0-14 years. Annual caseload increased from 1,011 in 2021 to 11,752 in 2022, 10,669 in 2023 and 12,149 in 2024, with seasonal peaks during the monsoon period and progressively later peaks and longer epidemic tails over time. Poisson models showed decreasing growth rates across years (r=0.449 in 2021 to r=0.091 in 2024) with increasing doubling times, while decay rates remained broadly comparable (halving time ~4.4-6.0 weeks). Overall, 8.0% of cases required inpatient admission, 1.3% were referred, and four deaths were reported (case fatality <0.1%). In multivariable analysis, inpatient admission was associated with older age ([&ge;]60 vs 0-14: aOR 2.31), delayed presentation (aOR 1.06 per day), refugee status (aOR 1.39), presence of any World Health Organization (WHO) warning sign (aOR 26.60), low systolic BP (aOR 2.84) and chronic co-morbidity (aOR 6.07). In addition, males had lower odds of admission than females (aOR 0.88). NS1 antigen alone was positive in 62.1% of cases, IgM alone in 33.6%, and dual positivity in 4.3%. Longer delay from symptom onset to presentation was strongly associated with IgM-only positivity compared with NS1-only positivity (adjusted models controlling for age and sex). Conclusion: Sustained dengue preparedness is required in Coxs Bazar, including strengthened surveillance, community-based early referral, targeted monitoring of high-risk groups, environmental vector control, and phase-appropriate use of NS1 and IgM/IgG diagnostics to reduce missed diagnoses and prevent progression to severe disease. These findings highlight the need for a policy shift from episodic outbreak response toward sustained dengue preparedness in humanitarian settings, including strengthened surveillance systems, integrated diagnostic strategies, community-based early referral, and coordinated vector control interventions.

Attractive targeted sugar baits (ATSB) are a potential new class of vector control tool that act through an "attract and kill" mechanism on mosquitoes. We conducted a meta-analysis using data from three large-scale Phase III trials of the Westham Sarabi v1.2 ATSB (0.11% dinotefuran) conducted in Kenya, Mali, and Zambia, to determine the effect of the intervention on clinical malaria incidence in children, Plasmodium falciparum infection prevalence, and dominant vector species parity, abundance, landing rate, and sporozoite positivity. The Sarabi ATSB was deployed on exterior walls at the rate of two per residential structure. Aggregated and individual-level meta-analyses were completed for each of the six trial outcomes, comprising 6981 person-years of follow-up for clinical malaria incidence (primary epidemiological outcome) and 19443 Anopheles for parity assessment (primary entomological outcome). Post-hoc analyses included assessment of dose-response relationships between coverage-adjusted intervention density and clinical malaria incidence. There were no statistically significant differences between arms in any of the epidemiological or entomological outcomes. There was statistically significant evidence of a 19% reduction in clinical malaria incidence for every 10 bait stations per hectare increase observed in spatial density (IRR 0.81, 95% CI 0.74-0.89, p<0.001), provided that the ATSB were in good condition. This finding suggests that there may be deployment approaches or dosing strategies under which ATSB tools could be efficacious, although threshold spatial densities could not be determined from available data. This meta-analysis furthermore highlights important recommendations for future cluster-randomized trials of vector control interventions, including conducting comprehensive baseline data collection to identify cluster outliers or sites with differences in vector bionomics, and collecting a limited set of entomological outcomes in all trial clusters to ensure an adequately powered and balanced analysis of entomological effects.

Between 2015 and 2025, Cambodia reported a 99.9% decline in the number of cases of malaria. To aid acceleration of elimination, the National Center for Parasitology, Entomology and Malaria Control (CNM) implemented a package of interventions known as the Last Mile (LM) elimination program. The aim of this study was to determine the impact of the LM program on case numbers and evaluate the coverage of interventions. LM was rolled out between November 2020 and December 2023 in villages reporting a locally acquired case of Plasmodium falciparum or mixed infection with P. falciparum and P. vivax and included combinations of targeted drug administration (TDA), intermittent preventative treatment for forest goers (IPTf), active fever screening (AFS), the recruitment of a village or mobile malaria worker (VMW/MMW) and the top-up of insecticide-treated bed nets (ITN) depending on the vulnerability and receptivity of the village. A total of 103 full and 82 partial villages in seven provinces were included. Two rounds of TDA were administered, with a total of 10,678 individuals (67.6%) given during the first round and 9,678 (62.3%) during the second round. Coverage varied by province with none meeting the recommended threshold of 80%. IPTf was implemented each month among 35% (n=35) of full LM villages and 56% (n=42) of partial LM villages. A total of 11.7% (n=12) of full LM villages implemented AFS consistently on a weekly basis. Controlled interrupted time series showed no statistically significant difference in the number of malaria cases before and after the implementation of LM. Although we were unable to prove a statistically significant impact of LM, likely due to the small number of cases prior to LM, it is important to add to the limited evidence-based for Accelerator Strategies in countries approaching the elimination of malaria. Furthermore, findings from the feasibility and impact of individual interventions were used to change policy at the national level.

Background Approximately 59,000 cases and 1700 deaths were reported during the 2022-2023 cholera outbreak in Malawi. In response, the Ministry of Health implemented Oral Cholera vaccination campaigns (OCV) as one of the interventions. Four series of single-dose reactive OCV campaigns were conducted in 21 health districts between May 2022 and September 2023. OCV survey report of 2023 estimated a coverage of 55.40%. It was barely known how a single dose of OCV interrupts community transmission. This study was conducted to provide evidence on the use of a single-dose strategy and its contribution towards reducing the risk of cholera infection. Method A cross-sectional quantitative analysis was conducted to assess the effectiveness of OCV in reducing cholera incidence, severity, and mortality during the 2022-2023 cholera outbreak in Malawi. A national cholera line-list was used for analysis. Results Oral cholera vaccination coverage was at 2.0% of 28,920 suspected cholera cases. The effectiveness of a single dose of OCV towards reducing cholera infections was 98.00%. and associated with lower odds of severe dehydration (OR = 0.50; 95% CI: 0.39-0.64), with OCV effectiveness at 50%(95% CI: 36-61) Case fatality rate among vaccinated was 1.20 (95% CI: 0.54; 2.6, p = 0.025) and among unvaccinated it was 2.80% (95% CI: 2.6; 3.0, p = 0.025). Conclusion A single dose of the OCV campaign conducted during the 2022-2023 cholera outbreak in Malawi contributed to the reduction of cholera incidence. The intervention complemented other long-term interventions such as Water, Sanitation and Hygiene Oral Dehydration Points, Case Area Targeted Intervention, and Risk Communication and Community Engagements.

Abstract Background In many countries, particularly in sub-Saharan Africa, medical pluralism and utilization of multiple therapeutic approaches for managing diseases, including malaria, are common. Ghana's antimalarial medicine policy has recommended herbal medications for treating uncomplicated malaria. While this is in line with complementary and alternative medicine (CAM) use for the treatment of malaria, exploring CAM for malaria prevention could be an important consideration for public health initiatives towards malaria elimination efforts. This study assessed the prevalence, perceptions, and attitudes on CAM use for malaria prevention in the general population and associated factors. Methods A community-based cross-sectional analytic survey was conducted among 3064 adult residents sampled between September and November 2023. A multi-stage sampling method was used to select participants from 18 sub-districts drawn from 6 districts and 6 regions in Ghana. Data on CAM use for malaria prevention, attitudes about CAM, perceptions about malaria, and sociodemographic factors were collected. The primary outcome was reported CAM use for malaria prevention within the 12months preceding the survey, measured as a binary outcome. Multiple logistic regression analyses were performed to identify the predictors of CAM use for malaria prevention. Results A total of 3,064 household respondents were involved in the analysis, with 51.2% (n=1,570) females and a median age of 31 years (IQR: 24-42 years). The use of CAM for malaria prevention in the last 12 months was 31.6% (95% CI: 30.0-33.3%). The most common types of CAM used included botanical/herbal medicine (21.8%), vitamin supplements (12.3%), mineral supplements (10.7%), and spiritual healing/prayers (9.6%). Increased CAM use for malaria prevention was associated with education and perceptions, such as concerns and consequences about malaria. Factors associated with decreased odds of CAM use included formal employment and having a skeptical and indifferent attitude about CAM. Conclusion Over a third of the population used CAM for malaria prevention in the last year, highlighting its role in public health. Integrating herbal medicine into prevention strategies could enhance community acceptance and help with efforts toward malaria elimination. However, further research is needed to validate clinical efficacy, establish potential drug-herb interactions, and isolate lead compounds for optimized malaria prevention therapy.

BackgroundControl of Aedes aegypti, the primary vector of dengue and other Aedes-borne viruses, is challenged by insecticide resistance, limited efficacy of existing tools and the large and widespread epidemics. Targeted Indoor Residual Spraying (TIRS), a modification of traditional indoor residual spraying focused on Ae. aegypti resting sites, has demonstrated promising results, yet its indirect community-wide effects remain underexplored. Methodology/Principal FindingsWe conducted an entomological cluster-randomized controlled trial in Iquitos, Peru, to evaluate the direct and indirect entomological impacts of TIRS using pirimiphos-methyl. Thirty clusters were randomized to receive either TIRS (15 clusters, 898 structures) or standard Ministry of Health vector control activities (15 clusters, 1,018 structures). Aedes aegypti indoor densities were assessed in the 45 days pre-intervention and at four time points up to 255 days post-intervention using Prokopack aspiration. Generalized linear mixed models with a negative binomial link were used to estimate incidence rate ratios (IRRs) and calculate efficacy (1-IRR) for houses that received TIRS (direct effect) and untreated houses in TIRS clusters (indirect effect). Direct efficacy reached 96% at 15 days post-spraying and remained significant (40%) at 255 days post-spraying. Indirect efficacy reached 69% at 15 days and declined to 7% by 255 days post-spraying. Despite only 57% household-level TIRS coverage, both direct and indirect impacts on Ae. aegypti were significant during early post-intervention surveys, and after 8 months in TIRS clusters. Conclusions/SignificanceTIRS provided substantial and sustained reductions in indoor Ae. aegypti density, including measurable indirect effects in untreated homes within intervention clusters. These findings demonstrate the entomological value of TIRS even at moderate coverage levels and highlight its potential for both preventive and reactive vector control programs and should be considered for implementation by Ministries of Health in dengue-endemic urban settings as well as by the U.S. military when deployed to tropical or subtropical locations.

Rectal artesunate (RAS) is a pre-referral intervention recommended for children with suspected severe malaria in remote settings where injectable treatment is not readily available. Although clinical trials have demonstrated efficacy, less is known about the behavioural and health system factors influencing effectiveness under routine conditions. A convergent parallel mixed-methods design was used to assess implementation of Zambia's RAS intervention package across three districts: Serenje, Chama, and Mwinilunga. A retrospective case-tracking investigation of all 300 children with suspected severe malaria recorded by community health workers (CHWs) assigned to study facilities examined progression and attrition across the severe malaria care cascade. In-depth interviews and focus group discussions with caregivers, CHWs, and other stakeholders explored barriers and facilitators influencing progression. Among 300 enrolled children, early attrition occurred due to negative rapid diagnostic test results. Of 239 RDT-positive children, 218 (91.2%) received RAS. Referral completion was lower; among 261 children referred and followed up at health facilities, 209 (80.1%) were confirmed to have completed referral. Of 186 children diagnosed with severe malaria at the facility, 167 (89.8%) received both injectable artesunate and follow-on artemether-lumefantrine. Patterns of disengagement varied by district, with Serenje demonstrating the most consistent progression, Chama experiencing the largest drop-off at RAS administration, and Mwinilunga showing the lowest completion of follow-on treatment. Qualitative findings revealed strong community appreciation for RAS despite stockouts, alongside social and behavioural barriers, including gendered responsibilities, transport challenges, and confusion following symptom improvement, that discouraged referral completion. RAS can be a life-saving intervention when embedded within strong health systems and community structures. Zambia's experience underscores the need for comprehensive implementation strategies that extend beyond drug distribution to include sustained CHW training, reliable commodity supply, functional referral systems, and meaningful caregiver engagement.

Background: Malaria remains a major global health threat, with 249 million cases and 609,000 deaths reported in 2022. The Ashanti Region of Ghana bears a disproportionate burden, with severe malaria accounting for 24% of hospital admissions in 2021, above the national average of 19%. Despite intensified control efforts, inpatient mortality patterns remain poorly understood. This study identifies key determinants of severe malaria mortality among hospitalized patients in the Ashanti Region. Methods: We analyzed inpatient surveillance data from the District Health Information Management System 2 (DHIMS2) for severe malaria admissions from 2018 to 2022. Descriptive statistics, bivariate analyses with robust survey estimation (accounting for design effects), and multivariable Firth penalized logistic regression were used to identify mortality predictors. Survey-adjusted logistic regression served as a sensitivity analysis to validate findings. Results: Among 54,544 severe malaria admissions, females comprised 51.1% and children under five 39.4%. The case fatality rate was 0.4% (200 deaths). Mortality was significantly associated with age, occupation, insurance status, facility ownership, admitting department, length of stay, and comorbidities. Males had 1.4 times higher mortality odds than females. Compared to children under five, patients aged 5 to 17 years had 44% lower odds of mortality (aOR = 0.56, 95% CI: 0.33, 0.94). Active NHIS membership had lower mortality odds by 67% (aOR=0.33, 95% CI: 0.25, 0.45) compared to inactive membership. Admissions to faith-based facilities showed lower mortality odds (aOR=0.38, 95% CI: 0.23, 0.65) than government facilities, while medical wards had higher odds (aOR=2.38, 95% CI: 1.48, 3.84) than paediatric wards. Stays of 3 to 5 days were associated with lower mortality odds (aOR=0.67, 95% CI: 0.47, 0.97) compared to stays <3 days. Those with comorbidities had twice the mortality odds versus those without. Sensitivity analysis confirmed consistent direction and significance. Conclusion: Age, comorbidities, insurance coverage, facility type, and admission practices strongly influence severe malaria mortality in Ashanti. Strengthening NHIS enrollment, extending inpatient monitoring beyond three days, and adopting best practices from paediatric and faith based facilities could improve survival. Integrating comorbidity screening and management into malaria protocols is essential to reducing preventable deaths.

Background: Household insecticides are widely used for domestic pest control, yet exposure patterns in traditionally underserved populations remain poorly characterized. In the Brazilian Amazon, data on use patterns among older adults living in riverine communities are particularly scarce. Objective: To describe the prevalence, frequency, duration, application practices, and types of household insecticides used by older adults living in near-urban riverine insular communities in the Brazilian Amazon. Methods: Cross-sectional, population-based door-to-door survey conducted from August 2022 to July 2025 in four islands (Cotijuba, Mosqueiro, Outeiro, and Combu) in the city of Belem, Brazil. All residents aged 60 years or more registered in the primary care system were invited to participate. Trained interviewers administered an in-person standardized questionnaire to participants on current household insecticide use, frequency, duration, self-application, protective equipment, insecticide types, and product brands. Results: Among 1,101 screened individuals, 1,084 were included (median age at evaluation: 68 years). Overall, 78.4% reported current use of household insecticides. Weekly or more frequent use was reported by 58.9%, and 33.4% reported use for more than 5 years. Self-application was common (57.5%), whereas use of protective equipment was rare (8.2%). Aerosol sprays were the most frequently reported type (39.4%). Commonly recalled aerosols contained pyrethroid mixtures including cypermethrin, imiprothrin, prallethrin, and transfluthrin. A substantial proportion of participants reported using unregulated products and veterinary-only insecticides for household purposes. Conclusions: Household insecticide use is highly prevalent and frequent in Amazonian riverine communities, with minimal use of protective equipment and substantial irregular practices, underscoring the need for targeted risk communication and surveillance.

BackgroundMalaria remains a leading public health burden in sub-Saharan Africa, disproportionately affecting children under five years. In response, Kenya introduced the RTS,S/AS01 malaria vaccine in selected regions, including Siaya County where malaria transmission is endemic. Despite this milestone, uptake has been inconsistent, with hesitancy emerging as a significant barrier. ObjectiveThis study aimed to determine factors associated with malaria vaccine hesitancy among caregivers of children 6-59 months in Ugenya Subcounty, Siaya County. MethodologyA cross-sectional mixed methods design was employed involving 425 caregivers and 15 healthcare workers and County health officials between January to February 2025. Quantitative data were collected using structured questionnaires and analyzed in Stata version 17 through descriptive statistics, bivariate analysis at 20% significance threshold, and multivariable logistic regression at 5% level to determine key factors associated with malaria vaccine hesitancy. Qualitative data from 15 key informant interviews were transcribed verbatim and thematically analyzed using NVivo. Thematic analysis, guided by a predefined codebook, was used to identify recurring patterns and extract key themes, which were illustrated with direct quotations from participants ResultsOverall, 42.9% of caregivers (n=181; 95% CI: 38.9%-47.3%) reported hesitancy. Significant predictors included caregiver age, marital status, family size, access to health facilities, and vaccine availability. Single caregivers, those from smaller households, and those facing health facility access challenges were more likely to be hesitant to malaria vaccine. Despite high levels of knowledge, misconceptions and misinformation about vaccine safety, often spread via social media persisted. Conversely, caregivers relying on healthcare workers and mainstream media showed greater acceptance of malaria vaccine. Conclusion and RecommendationsMalaria vaccine hesitancy remains significant at 42.9%, driven by demographic factors such as younger age, single status, and smaller household size. Structural barriers including limited vaccine availability and poor access to health facilities further contribute to reluctance. Although knowledge and awareness were high, misinformation, particularly from social media, persisted, while information from healthcare workers improved acceptance. Addressing these gaps through targeted community engagement, improved access, and trusted communication channels is essential to increase uptake of malaria vaccine.

Background Malaria remains a critical global health challenge, with over 68% of Ethiopias population living in at-risk areas. While Long-Lasting Insecticidal Nets (LLINs) are a cornerstone of prevention, their effectiveness depends on consistent use. This study aimed to assess LLIN ownership and utilization patterns and identify socio-behavioral and physical determinants of their effectiveness in endemic communities. Methods A community-based, cross-sectional survey was conducted from October 2024 to January 2025 across 11 administrative regions in Ethiopia. Using a two-stage stratified cluster sampling technique, data were collected from 9,222 households (34,427 individuals) through face-to-face interviews and direct physical observations. Data analysis was performed using the SPSS Complex Samples module and hierarchical multivariable logistic regression. Results The survey found a household LLIN ownership rate of 71.5%, while the proportion of sufficient LLINs for every two people was 58.3%. Among those who owned nets, the overall utilization rate was 59.9%, with significantly higher rates in rural areas (72.7%) than in urban areas. Vulnerable groups achieved higher usage levels, specifically pregnant women (78.5%) and children under five (67.2%). Multivariable analysis indicated that age and pregnancy status were the strongest predictors of LLIN use, with ORs of 0.258 (p < 0.001) and 0.662 (p < 0.001), respectively. Major barriers identified included a 60.5% lack of confidence in hanging nets (p < 0.001) and a widespread misconception (64.1%) that malaria risk is restricted to the rainy season. Conclusion Although Ethiopia has made strides in LLIN ownership and prioritized protection for vulnerable demographics, overall utilization remains below the 80% threshold required for community-wide protection. To bridge the gap between ownership and consistent use, national strategies should transition toward skill-based interventions and targeted communication to address practical barriers and seasonal misconceptions.

Maternal health during pregnancy is critical for favorable birth outcomes and long-term wellbeing of both mothers and infants. Women in rural, malaria-endemic regions face unique biological and socioeconomic challenges that may increase the risk of adverse pregnancy outcomes (APOs). This study investigated the incidence and determinants of APOs among pregnant women attending antenatal care at Webuye sub-County Hospital in Western Kenya, a rural malaria-endemic setting. We conducted a retrospective cohort analysis utilizing previously collected data of 300 women enrolled during early pregnancy and followed through delivery. Maternal demographic, clinical, and infection-related factors were assessed, and associations with APOs were evaluated using chi-square tests and multivariable logistic regression. Maternal age and gestational age at enrollment were significantly associated with malaria history (P<0.001). Maternal BMI abnormality (124.5/1000 pregnancies), anemia (99.3/1000), fetal or neonatal death (81.3/1000), and preterm birth (43.8/1000) were observed (all P<0.001), suggesting a substantial burden. Younger mothers (<20 years) and older mothers (>35 years) were significantly more likely to develop anemia (P =0.026), and prior malaria infection further increased anemia risk (P =0.02). Abnormal urinalysis findings indicative of urinary tract infection were significantly associated with low birthweight (P =0.031). No significant associations were found between APOs and infant sex, parity, gravidity, or maternal ABO blood type. These findings highlight a substantial burden of APOs in this rural population, exceeding national and global estimates. Strengthening malaria prevention, nutritional support, urinary infection screening, and encouraging early antenatal care attendance are critical to improving maternal and neonatal outcomes. Targeted interventions for adolescent and older mothers, along with enhanced point-of-care diagnostics, may reduce preventable complications in similar resource-limited, malaria-endemic settings.

BackgroundDengue remains a major public health challenge in Thailand despite decades of vector control implementation. While mathematical models have explored dengue transmission dynamics, systematic evaluation of current control strategies under realistic operational conditions remains limited. MethodsWe developed a temperature-dependent, multi-serotype dengue transmission model that explicitly incorporates three primary vector control strategies: reduction in mosquito biting rates through personal protection measures, further reduction in mosquito birth rates beyond current larval control efforts, and further increase in adult mosquito mortality beyond current adulticide application levels. Using Approximate Bayesian Computation with Sequential Monte Carlo (ABC-SMC), we fitted the model to dengue hemorrhagic fever (DHF) surveillance data from nine province-year combinations representing high (Rayong), moderate (Ratchaburi), and low (Phrae) transmission settings across three years (2006, 2015, and 2017). The model accounts for four dengue serotypes, temperature-dependent mosquito dynamics, and temporary cross-protective immunity between serotypes. ResultsThe model closely reproduced observed monthly DHF case counts across all nine province-year combinations. Estimated reporting proportions ranged from 1.4% to 16.7%, with the highest values occurring in high-transmission provinces during the 2015 outbreak year. When each strategy was independently intensified by 50% relative to fitted baseline levels, reducing mosquito biting rates and increasing adult mosquito mortality consistently produced greater reductions in transmission than reducing mosquito birth rates. In the highest-transmission scenario (Rayong, 2015), a 50% reduction in biting rate from the baseline level yielded a 96.4% reduction in cumulative infections (95% CrI: 95.4-97.3%), compared with 94.3% (95% CrI: 91.8-95.6%) for a 50% increase in adult mosquito mortality and 77.0% (95% CrI: 58.6-84.6%) for a 50% reduction in mosquito birth rate. Analysis of the time-varying reproduction number (Rt) confirmed that interventions targeting adult mosquito-human contact achieved the greatest sustained epidemic suppression, although the relative ranking between bite prevention and adulticide application varied by epidemiological setting. ConclusionsUnder the uniform 50% intensification scenario tested, interventions that directly disrupt adult mosquito-human contact, whether through personal protection or adulticide application, substantially outperformed larval control in reducing dengue transmission across diverse Thai settings. These findings support prioritizing personal protection and adulticide application, while the generalizability of this ranking to other intensification levels and settings warrants further investigation.

Protracted conflict in Sudan since April 2023 has severely disrupted routine immunization services, particularly in the Darfur region, resulting in widespread vaccine stockouts, declining coverage, and increased risk of vaccine-preventable disease outbreaks. Traditional national supply routes became largely inaccessible, exacerbating inequities in immunization access for conflict-affected and displaced populations. This paper examines the design, implementation, and outcomes of a cross-border vaccine deployment strategy implemented in 2025 through Chad to restore vaccine availability in Darfur. Using programmatic data, shipment records, coverage reports, and partner monitoring outputs, the study assessed the operational feasibility, partnership arrangements, and public health impact of the intervention on routine immunization and outbreak response. In 2025, nearly 20 million doses of vaccines were successfully delivered to the five Darfur states through cross-border operations, supporting routine immunization services and outbreak response campaigns. Average coverage for the first dose of a DPT-containing vaccine (DPT1) increased from 22.6% in 2024 to 83.2% in 2025, while DPT3 and MCV1 coverage rose to 55.4% and 50.4%, respectively. Oral cholera vaccine campaigns achieved 90.4% coverage among targeted populations, and polio outbreak response campaigns exceeded 100% administrative coverage, reflecting both successful reach and uncertainties in target population estimates due to population displacement. Investments in cold chain infrastructure and strengthened coordination among government, UNICEF, Gavi, and implementing partners were critical to these outcomes. The findings demonstrate that cross-border vaccine deployment can serve as a viable and effective mechanism for restoring immunization availability and support recovery of immunization service delivery in a highly constrained conflict setting. While not a substitute for functional national systems, such approaches are essential life-saving interventions during acute crises and should be integrated into preparedness planning for fragile and conflict-affected contexts.

Background Accurate hemoglobin (Hb) measurement is essential for determining anemia prevalence at the population level. The HemoCue method, commonly used in resource poor settings, has been shown to overestimate Hb levels compared to the direct cyanmethemoglobin (DCM) method, leading to an underestimation of anemia. This study aimed to validate the HemoCue method against the DCM method and establish an optimal cut-off value for diagnosing anemia in children under two. Methods Date were collected from children under two years of age as part of the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development study in Bangladesh, conducted in Mirpur, Dhaka, from February 2010 to February 2017. Using HemoCue 201 instrument and DCM method, Hb levels was measured in 846 venous blood samples collected from 589 children. Youdens Index was used to identify the optimal cut-off for hemoglobin. While it provided a strong threshold, we prioritized achieving at least 70% sensitivity and specificity to confirm balanced diagnostic performance. Results The median (IQR) Hb concentrations estimated by HemoCue and DCM were 11.6 (10.5, 12.5) g/dL and 10.8 (10.1, 11.5) g/dL, respectively. Using a cut-off of <10.5 g/dL for anemia, the prevalence was significantly higher with the DCM method (35.2% vs. 23.2%). Considering DCM as the gold standard, the sensitivity and specificity of the HemoCue method were found to be 93% and 53%, respectively. In the test/train analysis, the newly identified cut-off of 11.00 g/dL, indicated an anemia prevalence of 34.2% in the testing dataset, with a sensitivity of 84% and specificity of 69%. Conclusion This study underscores the discrepancies between the HemoCue and DCM methods for measuring Hb levels. By proposing and validating a new cut-off value, we provide a more accurate means of diagnosing anemia in children under two.

Background In 2017, Zambia adopted surveillance as a core intervention towards achieving malaria elimination. Among the surveillance strategies is the malaria case investigation and response 1-3-7 (MCIR 1-3-7), which has been piloted in two low-incidence districts in the Southern Province since 2021. The study aimed to assess the implementation of MCIR 1-3-7 under programmatic conditions. It examined the timeliness, and completeness of the MCIR 1-3-7 activities, including the completeness of data entry in surveillance forms, and explored the experiences and perspectives of healthcare workers involved in the pilot. Methods A mixed-methods design was employed to assess the MCIR 1-3-7. Using a descriptive cross-sectional design, quantitative data were collected from 19 healthcare facilities in the two districts to assess the timeliness and completeness of MCIR 1-3-7. Additionally, 12 qualitative interviews were conducted with 29 healthcare workers from 11 of the 19 healthcare facilities. The interviews were voice-recorded and then transcribed manually. A codebook was developed using an iterative process to explore the facilitators and barriers encountered by healthcare workers in implementing the MCIR 1-3-7 intervention. All the visited facilities were purposively selected based on logistical convenience. Results This study retrospectively assessed 510 malaria cases that were diagnosed between January 2022 and June 2023, presenting at 19 health facilities: 283 cases in Chikankata and 227 in Mazabuka districts. A total of 278 cases (54.5%) were deemed to have been imported from outside the district, province, or country, while 45.5% (232/510) of the cases were classified as transmitted locally. Overall, 29.6% of case notification forms were found to be complete. Twelve interviews with 29 healthcare workers revealed a lack of transportation modalities as the main obstacle in executing the MCIR 1-3-7 intervention. The healthcare workers also indicated that monetary incentives, and supportive supervision would help them succeed in implementing this intervention. Conclusions The MCIR 1-3-7 has the potential to accelerate elimination in areas with low-transmission of malaria in Zambia. This study highlights opportunities to improve future implementation of the MCIR 1-3-7 intervention via strengthening supportive supervision, availing job aids, and ensuring access to malaria commodities as the intervention expands.

BackgroundAnimal bites represent a significant public health concern due to the risk of injuries and transmission of zoonotic diseases such as Rabies, particularly in low and lower- middle-income countries (LMICs). Understanding the epidemiological characteristics of animal bite incidents is essential for improving the prevention and control strategies. This study aimed to characterize the epidemiological patterns and characteristics of animal bite cases in Sylhet, Bangladesh. Methodology/Principal findingsWe conducted a retrospective analysis of 6,565 animal bite cases reported between January 1 and December 31, 2024, in Sylhet, Bangladesh. Data on demographic characteristics, type of biting animal, site of bite, and exposure category were collected and analyzed to determine associations using correlation analyses and chi-square tests. Among the victims, 3,917 (60%) were male and 2,648 (40%) were female and young adults aged 20-39 years comprised the largest group (39% of cases). The majority of cases (88.1%) originated from urban areas within Sylhet City Corporation. Cats were the leading cause of bites (56.6%), followed by dogs (35.0%) and monkeys (7.5%), suggesting a shift from the traditional dog-dominated pattern. The most frequently affected anatomical sites were the legs (50.3%) and hands (40.9%). Most exposures were classified as World Health Organization (WHO) Category II (98.2%). Bite incidents showed moderate seasonal variation, with peaks in spring and early autumn. A significant declining temporal trend was observed for monkey bites (R = -0.59, p = 0.044), whereas cat and dog bite patterns remained relatively stable throughout the year. Significant associations were identified between bite site and age group, as well as between biting animal and demographic characteristics (p < 0.05). Conclusion/SignificanceThese findings highlight the epidemiological patterns of animal bites in Sylhet and emphasize the need for strengthened public awareness, surveillance, and preventive strategies to reduce animal bite incidents and associated zoonotic disease risks. SynnopsisO_LIA large-scale retrospective analysis of 6,565 animal bite cases revealed a cat-dominant bite pattern (56.6%), contrasting with the traditional dog-dominant paradigm in South Asia. C_LIO_LIYoung adults (20-39 years) and males (60%) were disproportionately affected, reflecting occupational and behavioral exposure risks. C_LIO_LIUrban residents (88.1%) accounted for the majority of cases, highlighting the growing public health burden of animal bites in rapidly urbanizing settings. C_LIO_LIThe most frequently affected anatomical sites were the legs (50.3%) and hands (40.9%). Bite incidents showed moderate seasonal variation, with peaks in spring and early autumn. C_LIO_LICategory II exposures (98.2%) predominated, indicating a high burden of seemingly minor injuries that may be underestimated in rabies prevention strategies. C_LI

Background: Dengue is a major public health problem in Brazil, and Minas Gerais is one of the states with the highest burden. In January 2019, the Brumadinho dam collapse released about 12 million cubic meters of iron ore tailings into the Paraopeba River basin, causing environmental disturbance that could plausibly affect vector habitats and dengue transmission. We evaluated the spatiotemporal dynamics of dengue in Minas Gerais from 2014 to 2023 and tested whether the disaster was associated with changes in affected municipalities. Methods: We performed an ecological spatiotemporal analysis using dengue notifications from SINAN for all municipalities in Minas Gerais (2014-2023). Municipalities were classified as Paraopeba basin, regional controls, or state controls. Temporal similarity was assessed using Pearson correlation-based hierarchical clustering and non-metric multidimensional scaling (NMDS). Sources of variation were examined with PERMANOVA and principal component analysis (PCA). A linear mixed-effects model with municipality as a random effect was used to test changes after 2019, with pre/post contrasts estimated from marginal means. Results: Dengue showed strong temporal synchrony across the state, with major epidemic peaks in 2015-2016, 2019, and 2023. Health region explained 31.5% of the variation in temporal incidence profiles (p = 0.001), whereas Paraopeba basin status explained no significant variation (p = 0.998). No temporal cluster was enriched for municipalities in the Paraopeba basin. PCA identified 2023, 2019, and 2016 as the main years driving variability. In the mixed model, year was significant (p < 0.001), but Paraopeba basin status and its interaction with time were not. Incidence increased significantly after 2019 in non-exposed municipalities (p < 0.001), but not in basin municipalities (p = 0.088). Conclusions: Dengue dynamics in Minas Gerais were driven mainly by regional and state-wide epidemic processes, with no significant independent effect of the Brumadinho dam collapse on notified dengue patterns.

Effective filtration and concentration of stool specimens is an essential pre-analytical step for reducing fecal debris and improving organism recovery using microscopy-based ova and parasite (O&P) examination. This study evaluated three commercially available fecal sedimentation-based filtration/concentration systems, ParaPak SpinCon (Meridian Bioscience), Mini Parasep SF (Apacor), and the newly-available ParadeviceReingenuity), for qualitative parasite detection and workflow logistics using conventional and artificial intelligence (AI)-assisted microscopy. Forty clinical stool specimens (20 parasite-positive and 20 parasite-negative) were processed with the 3 devices, and the resultant 120 wet mount and 120 trichrome stained smear preparations were examined using conventional microscopy. Trichrome-stained slides were also scanned at 40x magnification using a Hamamatsu NanoZoomerS360 flatbed digital slide scanner and images were analyzed using the Techcyte Fusion Human Fecal Trichrome AI algorithm. Positive and indeterminate digital findings were confirmed by conventional glass slide microscopy. Slides and digital images were reviewed in a blinded manner. Concordance was assessed among the 360 initial evaluations (microscopy and AI-assisted), and discrepant parasitology results were resolved through re-review and specimen reprocessing as needed. Final qualitative agreement across slide/image evaluations using all three concentration systems was 100%. Minor discrepancies in protozoan and white/red blood cell detection/identification were noted in 5 and 7 cases, respectively, and likely reflected sampling and observer variability. While the three concentration systems produced equivalent qualitative results, the Paradevice and Mini Parasep SF offered the most streamlined workflows. These findings support the Paradevice and Mini Parasep SF as efficient, analytically equivalent systems that are compatible with traditional and AI-assisted O&P workflows.