Tropical Medicine and Infectious Disease
○ MDPI AG
Preprints posted in the last 90 days, ranked by how well they match Tropical Medicine and Infectious Disease's content profile, based on 12 papers previously published here. The average preprint has a 0.02% match score for this journal, so anything above that is already an above-average fit.
Sharkey, T.; Nyombayire, J.; Parker, R.; Ingabire, R.; Umuhoza, C.; Bizimana, J.; Mukamuyango, J.; Unyuzimana, M. A.; Mazzei, A.; Tichacek, A.; Allen, S.; Karita, E.; Wall, K. M.
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Reproductive tract infections (RTI) are associated with adverse outcomes in pregnant African women. However, many diagnostic strategies are unaffordable or perform poorly. Here, we assess RTI prevalence and predictors of chlamydia/gonorrhea (CT/NG) in pregnant women reporting vaginal discharge and the performance of our previously published CT/NG risk algorithm in this population versus Rwandan National Guidelines (RNG). From 2017-2020, free sexually transmitted infections (STI) services were provided to residents in Kigali, Rwanda. Medical history and gynecologic examination were done. Laboratory assessments included HIV; syphilis; microscopy for trichomoniasis, bacterial vaginosis (BV), and candida; and PCR for CT/NG. Eighty-seven pregnant women received STI services. Prevalence was 28% for CT/NG, 15% for trichomoniasis, 24% for BV, 39% for candida, and 79% for any RTI. Predictors of CT/NG were age <=25 (adjusted prevalence odds ratio [aPOR]=4.92; 95% confidence interval [CI]: 1.52-15.90; p=0.008), inconsistent condom use (aPOR=4.86; 95%CI: 0.98-24.10; p=0.053), absence of candida (aPOR=4.23; 95%CI: 1.13-15.82; p=0.032), and endocervical inflammation/discharge (aPOR=4.91; 95%CI: 1.40-17.20; p=0.013). Our algorithm outperformed the 2019 and 2024 RNG (sensitivity: 92% versus 46% and 35% respectively). Pregnant women seeking STI services had high RTI prevalence. Our algorithm performed well. Algorithms tailored for pregnant women and including male partner risk factors should be explored.
Lim, R. M. M.; Arinaitwe, M.; Babayan, S. A.; Nankasi, A.; AtuhAire, A.; Namukuta, A.; Mwima, N.; Pedersen, A. B.; WEBSTER, J. P.; Lamberton, P. H.; Clark, J.
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Background/aims The World Health Organization (WHO) aims to eliminate schistosomiasis as a public health problem (EPHP) across 78 endemic countries by 2030. However, for low-prevalence settings that reach EPHP, guidance on managing transmission to maintain EPHP or move towards Interruption of Transmission (IoT) is limited, partly due to insufficient evidence on drivers of resurgence. In Uganda, some communities inland from Lake Victoria have achieved EPHP for Schistosoma mansoni but not progressed to IoT. This study explored whether routine, short-range travel to the highly endemic lake could sustain transmission in these settings. Methods We conducted a cross-sectional study in five Ugandan villages ~5 km from Lake Victoria. Parasitological data were collected using Kato-Katz and Point-of-Care Circulating Cathodic Antigen tests, alongside questionnaires on lake travel from 585 individuals aged 1-91 years. A structural causal model estimated the total and direct effects of travel frequency, activity type, water contact duration, and drug treatment history on infection. Bayesian regression models and counterfactual simulations predicted infection under hypothetical interventions. Results Reaching IoT in low-risk villages may be undermined by habitual, short-range travel to high-risk sites, driven by the nature and duration of lake contact. Daily lake travel caused a 1.7-fold increase in odds of infection, while occupational activities caused a 3.4-fold increase compared with no lake activity. Counterfactual analysis showed that removing lake contact duration most reduced infection risk among moderate-frequency travellers, while daily travellers showed smaller changes, and some transmission persisted among individuals with little or no lake contact. Simulations demonstrated that modifying lake contact behaviours could reduce individual infection risk but had limited population-level impact. Conclusion These findings indicate that targeting only high-risk villages or individual behaviours is unlikely to achieve sustained, wide-spread IoT, underscoring the need for integrated control strategies that account for mobility, behaviour, and local transmission ecology.
Mafulu, Y. M.; Williams, V.; Ndlovu, P.; Ndabezitha, S.; Maseko, K. L.; Ndlovu, N.; Gwebu, S.; Matsenjwa, N.; Deku, B.; Mhlanga, N.; Dube, N.
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1.IntroductionSexually transmitted infections (STIs) represent a significant public health challenge globally, with the Southern Africa region experiencing particularly high rates. In Eswatini, the burden of STIs, including HIV, is alarming, necessitating effective prevention strategies. Pre-exposure prophylaxis (PrEP) has been introduced as a key intervention, yet its impact on condom use and STI prevalence remains underexplored. ObjectiveThis study aims to evaluate and compare condom use patterns and the prevalence of STIs among clients using PrEP and those who do not, among clients attending an STI Wellness Clinic in Eswatini. MethodsA prospective cross-sectional quantitative study will be conducted from February to June 2026 at the LaMvelase STI Wellness Centre. Participants will include HIV-negative individuals aged 15 and above, recruited through purposive sampling. Data will be collected via structured questionnaires and medical records, assessing condom use frequency, sexual behaviour, and STI rates. Laboratory testing will be conducted to confirm STI diagnoses. Statistical analyses will include descriptive statistics and logistic regression to identify associations between PrEP use and STI prevalence. ResultsThis protocol describes a study designed to assess the relationship between PrEP use, condom use behaviour, and STI prevalence among clients attending a specialised STI clinic in Eswatini. Findings will inform public health strategies and educational programs aimed at reducing STI rates and improving sexual health outcomes in Eswatini. ConclusionUnderstanding the dynamics between PrEP use and sexual health practices is crucial for optimising STI prevention strategies. This research will contribute valuable data to guide interventions and health policies and to design more effective intervention strategies in high STI prevalence settings, ultimately supporting efforts to mitigate the impact of STIs and HIV in Eswatini.
Hossain, H.; Mohiuddin, A. S. M.; Islam, S.; Insan, M.; Ahmed, S.; Brishty, K. A.; Parvej, M.; Yadav, S. K.; Ahmed, S.; Das, S. R.; Rahman, M. M.; Rahman, M. M.; Paul, B.
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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
Kyomuhangi, I.; Otabil, K. B.; Acheampong, A.; Ofori, D. K.; Kudzordzi, P.-C.; Nyarko, P.; Fronterre, C.; Cheke, R. A.; Basanez, M.-G.; Hawkes, F.
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Progress towards elimination of onchocerciasis transmission is evaluated using entomological and serological indicators. The latter assesses anti-Ov16 IgG4 seroprevalence in children aged <10 years. A seroprevalence of <0.1% suggests that ivermectin Mass Drug Administration (MDA) can be stopped and post-treatment surveillance initiated, according to World Health Organization (WHO) guidelines. Surveillance of populations living in close proximity to vector breeding sites and first-line villages may mask spatial transmission heterogeneity. We mapped anti-Ov16 seroprevalence within a 25-km radius around a known Simulium damnosum s.l. breeding site in Asubende, Ghana, to assess its spatial patterns and their implications for serosurveillance. A cross-sectional survey was conducted in September-November 2024 in 30 settlements. Individuals aged [≥]3 years were recruited through convenience sampling. The Ov16 rapid diagnostic test (RDT) using dry blood spots was used to estimate overall and site-level seroprevalence. Generalized additive models were used to assess seroprevalence trends versus distance from the breeding site. Among 2,479 participants with valid RDT results, overall seroprevalence was 10.0% (95% CI: 8.9%, 11.3%) and increased with age. Seroprevalence varied across sites (0-24.4%) and declined with increasing distance from the breeding site. Among 584 children <10 years old, seroprevalence was 1.5% (95% CI: 0.7%, 2.9%). Adjusting for RDT sensitivity and specificity, seroprevalence in this age-group was 0.7%, (95% CI: 0%, 2.4%). Seropositive children were detected up to 18 km from the breeding site, but none were identified at it. The distance-related decrease in overall seroprevalence is consistent with spatial patterns in vector abundance at Asubende and implies higher cumulative exposure near the breeding site. The small number of children tested limited inference in this WHO target age-group. Detection of seropositive children away from, but not at, the breeding site highlights limitations of surveillance focused on first-line villages and supports broader spatial sampling to strengthen evidence for stop-MDA decisions. Author summaryAfter decades of onchocerciasis control using ivermectin, many countries hope to demonstrate that they have interrupted transmission of this vector-borne parasitic disease using serological surveys. It is unclear whether exposure to infection is spatially clustered around the riverine breeding sites of the blackfly vectors and therefore whether this is where serosurveillance should focus. To address this, we collected dried blood spots from 2,480 consenting participants aged 3-96 years old from 29 communities within a 25-km radius of a known blackfly breeding site in Asubende, Ghana. A rapid diagnostic test was used to test the blood spots for antibodies to the Onchocerca volvulus parasite. We found that overall seropositivity declined with increasing distance from the breeding site, which suggests that cumulative exposure is higher near the breeding site, where vector population is also high. However, seropositivity in children (3-10-year-olds, n= 584), which is indicative of recent transmission, was spatially distributed across the study area and found up to 18 km from the breeding site. These findings are relevant to serosurveillance sampling strategies intended to detect low levels of transmission, which could miss peripheral evidence of ongoing transmission if they are focussed at breeding sites and those villages closest to them.
KARIUKI, H. W.; Nyasore, S. M.; Muthini, F. W.; Mwangi, P. W.; Mwandi, J. M.; Makazi, P.; Mureithi, M. W.; Bulimo, W. D.; Wango, T. J. L.; Wanjala, E.; Mckinnon, L.; Njaanake, H. K.
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Background Urogenital schistosomiasis (UGS), caused by Schistosoma haematobium (S. haematobium), disproportionately affects women in sub-Saharan Africa and can lead to haematuria, anaemia, and urinary tract morbidity. Data on the prevalence in women of reproductive age remains limited in contrast to infection among school-aged children in Kenya. This study assessed the prevalence of UGS and its socioeconomic determinants among women in Kilifi County, Kenya. Methods: Urine samples (20-50 mL) were collected from each participant over three consecutive days. Day-one samples were tested for haematuria, proteinuria, nitrites, leukocytes, and pregnancy using dipsticks. On the other hand, 10 mL of urine was examined for S. haematobium eggs via urine filtration on all three days. Results: A total of 599 women aged 15-50 years were enrolled, with complete data available for 336. The mean age was 33 years; 57.7% were <35 years. Most participants were from rural Magarini Sub-county (63%) and engaged in crop farming (62.5%). Primary education was the highest level attained by 59.8% of participants. Frequent contact with stagnant water was reported by 92%. The overall prevalence of S. haematobium infection was 13.7% (95% CI: 10.2-17.8), higher in Magarini (14.9%) than in Rabai (12.0%), though not statistically significant. Younger age, primary education, and frequent water contact were associated with higher infection rates; however, after adjustment for covariates, haematuria showed the strongest independent association with infection. Women with haematuria were 25.2 times more likely to be infected (OR: 25.24, 95% CI: 7.07-82.63, p < 0.001); multivariate analysis confirmed haematuria as the sole significant predictor (OR: 20.83, 95% CI: 5.45-79.57, p < 0.001). Conclusion: UGS prevalence among women in Kilifi County is substantial, with variation between sub-counties. Haematuria demonstrated the strongest independent association with infection and may serve as a simple, non-invasive diagnostic marker. These findings underscore the pressing need for the integration of UGS screening into the reproductive health services and targeted interventions. Authors Summary UGS, caused by the parasitic worm Schistosoma haematobium, is a neglected tropical disease and remains a major public health problem in sub-Saharan Africa. Although control programmes in Kenya primarily target school-aged children, women of reproductive age are frequently exposed through daily water contact and may develop chronic urinary and reproductive health complications. However, data on the infection burden among adult women are limited. In this study, we assessed the prevalence of urogenital schistosomiasis and associated risk factors among women aged 15-50 years in Kilifi County, Kenya. Urine samples were collected over three consecutive days and examined for parasite eggs and indicators of urinary tract disease. We found that urogenital schistosomiasis affected more than one in ten women in the rural sub-counties where the study was conducted. Haematuria was strongly associated with infection and remained the most reliable predictor after accounting for other social and behavioural factors. These findings demonstrate that UGS is an under-recognised health issue among women and highlight the potential value of simple urine-based screening tools. Integrating UGS screening into existing reproductive health services could improve early detection and contribute to more inclusive disease control strategies.
Ejaz, M.; Ahmed, A.; Rizvi, S. H.; Rizvi, A. A.; Ali, F.; Haroon, A.
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Background: Sexual and gender minorities (SGM), including men who have sex with men (MSM) and transgender women, often face stigma, legal constraints, and limited access to sexual and reproductive health services. These conditions restrict prevention and care, increasing vulnerability to HIV and human papillomavirus (HPV) infections. While strong HIV-HPV interaction is documented in high-income settings, evidence from low- and middle-income countries remains limited. This study examines the burden, co-infection dynamics, and progression of HPV infection and anal dysplasia among MSM and transgender women in Pakistan. Methods: A cross-sectional study was conducted between September 2015 and October 2016 among men who have sex with men (MSM) and transgender women recruited from sexual health and antiretroviral therapy centers in Karachi. Eligible participants were aged [≥]18 years and self-reported anal sex within the past 6 months (N=298). Two anal specimens were collected for HPV DNA detection and genotyping using PCR, and anal squamous intraepithelial lesions (ASIL) were assessed cytologically using the Bethesda classification. Associations were estimated using Cox proportional hazards regression algorithms to derive prevalence ratios (PRs). Results: Among participants, 44% (n=133) were living with HIV. Overall HPV prevalence was 65.1%, rising to 87% among HIV-positive individuals compared to 48% among those without HIV ({chi}{superscript 2}p[≤]0.001). Likewise 28.9% of participants living with HIV were infected with two or more than two types of HPV as compared with 18.8% participants without HIV ({chi}{superscript 2}p[≤]0.001). HIV infection was strongly associated with HPV acquisition (adjusted PR 2.81, 95% CI 2.16-3.82). Among HPV-positive participants (n=194), 58.8% were co-infected with HIV. High-risk HPV was highly prevalent among those living with HIV (83.2% vs. 35.3% ({chi}{superscript 2}p[≤]0.001)), with HPV16 as the dominant oncogenic type. Multiple HPV infections were more common among HIV-positive individuals ({chi}{superscript 2}p[≤]0.001), and HIV seropositivity was 3.43 (95% CI: 2.55-3.51) times higher among those with high-risk HPV. Co-infected participants demonstrated prolonged smoking, longer duration of sex work, high-intensity sex work with limited condom negotiation, and higher prevalence of anal warts (all p<0.05). Anal dysplasia (ASIL) was present in 35% of participants and was higher among HIV-positive individuals (42.4% vs. 28.1%, p<0.001). HIV-HPV co-infection was independently associated with ASIL (adjusted PR 1.75, 95% CI 1.07-2.88), while high-risk HPV further amplified this risk (PR 3.04, 95% CI 1.75-5.26). Conclusion: These findings demonstrate a biological continuum in HIV-positive MSM and transgender women, where HIV increases HPV acquisition, persistence, and multiplicity, accelerating progression to anal dysplasia. This reflects a syndemic shaped by biological interaction and structural vulnerability. Integrating HPV screening and vaccination within HIV services is essential to interrupt progression to cancer in this high-risk population.
Moshi, H.; Msugupakulya, B. J.; Vahedi, M.; Glozah, F. N.
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BackgroundSchistosomiasis remains a significant neglected tropical disease of public health concern, particularly in Sub-Saharan African countries, including Ghana. For decades, school-based preventive chemotherapy (PC) has been the mainstay of schistosomiasis elimination in Ghana; however, implementation fidelity across districts falls below WHO recommendations, leading to persistent transmission. This study explores contextual factors that influence the implementation fidelity of school-based preventive chemotherapy for schistosomiasis in endemic districts. MethodsA phenomenological qualitative study design using a maximum-variation purposive sampling technique was conducted in two endemic districts (Gomoa East and Awutu Senya East) in Ghana, with 21 participants, six key informant interviews with district Neglected Tropical Diseases (NTDs) coordinators and School Health Education Program (SHEP) coordinators, and 15 in-depth interviews with head teachers and SHEP teachers. Recruitment of participants and data collection were conducted from 20/06/2025 to 30/07/2025 using semi-structured interview techniques and were thematically analyzed in NVivo version 15, guided by Braun & Clarke (2006). The thematic analysis blended inductive and deductive coding techniques; inductive allowed themes to emerge from the data, while deductive was guided by Damschroder et al. (2022) Consolidated Framework for Implementation Research (CFIR), and Carroll et al. (2007), a framework for implementation fidelity. ResultsImplementation fidelity was shaped by the interplay of sociocultural, organizational, and health system factors. Key barriers included socio-cultural beliefs and perceptions on treatment uptake, drug-related fears and adverse reactions, logistical constraints and resource limitations, lack of training and incentives for frontline implementers, inadequate community sensitization and engagement, and gaps in coverage and adherence to program protocols. Conversely, fidelity was much better in situations where awareness had been raised, the community was effectively engaged, frontline implementers were motivated, and collaboration was strong among the health and education sectors, suggesting that high fidelity can be achieved through a systemic response. ConclusionImplementation fidelity of school-based preventive chemotherapy is a context-dependent, system-driven process shaped by the complex interaction of socio-cultural and structural factors. Moving forward, to enhance fidelity and achieve sustained schistosomiasis control requires a shift toward a community-centered delivery approach that emphasizes community sensitization and engagement, reliable logistical support, effective training and motivation for frontline implementers, and intersectoral collaboration.
Gil-Salcedo, A.; Gazzano, V.; Arsene, S.; Durand, A.; Roger, S.; Prots, L.; Laurencin, N.; Chanard, E.; Duez, A.; Le Naour, E.; Bausset, O.; Ghali, B.; Strzelecki, A.-C.; Felloni, C.; Levillain, R.; Fargeat, C.; Lefrancois, S.; Feuerstein, D.; Visseaux, B.; Escudie, L.; Visseaux, C.; Leclerc, C.; Haim-Boukobza, S.
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BackgroundSince September 2024, France has implemented a national reform allowing prescription-free access (PFA) to sexually transmitted infection (STI) screening in medical biological laboratories (MBLs). This study aims to characterize the populations undergoing STI testing according to their access modality and evaluate the probability of test positivity in relation to testing pathway, sex, and age groups. MethodsWe conducted a cross-sectional analysis of all individuals screened for Chlamydia trachomatis, Gonorrhoea, human immunodeficiency virus (HIV), hepatitis B virus (HBV), and syphilis by treponemal-specific immunoassay (TSI) in Cerballiance MBLs between Mars 2025 and February 2026. Multivariable logistic regression models stratified by sex and adjusted for age and region assessed associations between screening modality and STI positivity. ResultsAmong 1,008,737 individuals included, 27.8% were under PFA and 72.2 under prescription-based access (PBA). PFA users were more frequently male (47.4% vs. 36.3%, p<0.001) and aged 20-39 years (34.0%, p<0.001). Overall positivity rates differed by modality: PFA was associated with higher detection of Chlamydia (4.6% vs. 3.6%). PBA group showed more positive cases of syphilis (3.4% vs. 1.2%), HBV (1.3% vs. 0.4%), and HIV infections (0.3% vs. 0.2%, all p<0.001). Co-infection and gonorrhoea proportions did not significantly differ between modalities. ConclusionsPFA substantially increased STI screening uptake, particularly among young adults and men, and enhanced detection of bacterial STIs. PBA remains essential for diagnosing viral and chronic infections. These findings highlight the complementary roles of both access strategies and support PFA screening as an effective public health intervention to broaden STI detection and reduce transmission.
Mafulu, Y. M.; Ndlovu, P.; Maseko, K. L.; Williams, V.; Ndabezitha, S.; Gwebu, S.; Matsenjwa, N.; Mhlanga, N.; Dube, N.; Ndlovu, N.; Deku, B.
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1.IntroductionSexually transmitted infections (STIs) remain a major global public health challenge, with a particularly high burden in Southern Africa. In Eswatini, the burden of STIs, including HIV, is alarming, necessitating effective prevention strategies. Understanding clients engagement with STI services and how they learn about and access these services is vital for effective public health communication and service delivery. AHF Eswatini has implemented multiple demand creation strategies to improve awareness and utilisation of Wellness Clinic services, but evidence remains limited on which approaches are most effective from the client perspective. ObjectiveThis study aims to assess clients awareness, preferences, and perceptions of marketing strategies used by the clinic to inform marketing, communication and engagement approaches. Specifically, the study will examine the main sources of awareness, preferred communication channels, perceived effectiveness of outreach activities, and the relationship between awareness and service utilisation. This manuscript reports the study protocol prior to initiation of participant recruitment and data collection. MethodsA cross-sectional analytical study will be conducted from February 2026 to June 2026 at the LaMvelase STI Wellness Centre. Participants will include clients attending the STI Wellness Centre regardless of HIV status. Individuals aged 15 and above will be recruited through systematic sampling after every 5th client interval. Data will be collected via structured questionnaires and medical records. Clients will be surveyed on how they learned about the clinic, service satisfaction, and preferred communication channels. Statistical analyses will include descriptive statistics, evaluation of marketing reach and effectiveness, and logistic regression to identify associations. The analysis will also compare awareness patterns across demographic and key population groups and explore alignment between client-reported awareness and the demand creation strategies implemented by AHF Eswatini. ResultsThis protocol describes a study designed to generate evidence on client awareness, communication preferences, and the effectiveness of marketing strategies for STI service utilisation. Findings will inform public health strategies and educational programs aimed at reducing STI rates and improving sexual health outcomes in Eswatini. The study is also expected to identify high-impact communication channels for different client groups and generate operational recommendations for improving demand creation efficiency. ConclusionThis research will contribute valuable data to guide interventions and health policies and to design more effective interventions and communication strategies in high STI prevalence settings, ultimately supporting efforts to mitigate the impact of STIs and HIV in Eswatini.
Kugler, M.; Mujumbusi, L.; Pickering, L.; Muhumuza, R.; Akugizibwe, M.; Obicho, E.; Apangu, T.; Umo, E.; Nuwamanya, S.; Ashraf, S.; Atim, S. A.; Thomson, E. C.; Lamberton, P. H. L.
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Crimean-Congo haemorrhagic fever virus (CCHFV) causes a viral zoonotic disease transmitted through tick bites and direct contact with infected blood or tissue of infected animals. Socio-ecological and behavioural risk factors for CCHFV exposure in Uganda remain poorly understood, which can lead to the omission of key risk factors in quantitative survey design and limit our wider understanding. In this study, we explored human-animal-tick interaction transmission risks in Uganda. We conducted 24 focus group discussions (FGDs) and 31 key-informant interviews (KIIs) across six environmentally and socio-ecologically diverse districts, between October 2023 and March 2024. Study sites were selected using K-prototype analysis, which combined environmental and socio-ecological variables to identify distinct clusters within Uganda. FGDs were conducted separately with groups of community leaders, men, women and teenagers with stratified purposive sampling. Medical doctors, veterinarians, traditional healers, district surveillance officers, and herdsmen were individually interviewed as key informants and purposively sampled. Data were transcribed and translated into English, and analysed thematically using iterative categorisation in NVivo 14. Most participants reported tick bites, some as frequently as every day. Close contact with animals was common, including sleeping next to them in the same building, largely due to concerns about animal theft. Less frequent but notable practices included slaughtering animals for consumption or sacrifice and interactions with wild animals during hunting. Slaughtering and butchering an animal which was sick or had died was reportedly performed by participants in most districts. Plucking and roasting engorged ticks was a practice described in the Kaabong and Arua districts of Northern Uganda. These practices and behaviours highlight potential key risks of CCHFV transmission and underscore the need for future studies to address specific behaviours, to quantify if, and to what extent, they present an exposure risk. Further work should include underlying reasons for the behaviours, which would help ensure that culturally appropriate interventions are targeted.
Loeb, K.; van Wyk, A.; Milner, K.; Lemaille, C.; Frederick, C.; Hunter, M.; Martens, B.; Lajoie, J.; Placide, M.; Rimoin, A. W.; Hoff, N. A.; Noyce, R.; Fowke, K. R.; Kimani, J.; Mckinnon, L.; Shaw, S. Y.; Stein, D. R.; Kindrachuk, J.
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Syphilis is a sexually transmitted and bloodborne infection caused by Treponema pallidum spp. pallidum. Given the paucity of data on syphilis in Kenyan sex workers and gay, bisexual, and other men who have sex with men (GBMSM), we conducted a retrospective study of syphilis seropositivity in female sex workers (FSW) and GBMSM in Nairobi, Kenya. Seropositivity testing of cryopreserved plasma samples showed that 11.1% (72/647) were positive. Syphilis seropositivity was associated with HIV status, and FSWs were disproportionately represented in the seropositive group (66/72, 92%). Here, we report a higher seropositive rate than in previous studies in Kenya, and ongoing community and surveillance supports are important for addressing the ongoing public health impacts of syphilis.
Forrer, A.; Obie, E. D.; Bong, R. A.; Ekanya, R.; Njouendou, A. J.; Nji, T. M.; Amuam, A.; Eyong, E. M.; Ndzeshang, B. L.; Nkimbeng, D. A.; Fombad, F. F.; Teghen, S.; Suireng, A.; Ashu, E. E.; Hamill, L.; Enyong, P.; Turner, J. D.; Wanji, S.; Taylor, M. J.
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Abstract Introduction Onchocerciasis is targeted for elimination with community-directed treatment with ivermectin (CDTI). Alternative strategies are needed in areas where transmission persists despite long-term CDTI and/or are co-endemic with loiasis. This study assessed the efficacy of 35-day treatment with 100mg doxycycline on Wolbachia density at 6 months and microfilaridermia and palpable nodules at 30 months post-treatment. Methods A treatment follow-up study was conducted in 20 high-transmission onchocerciasis communities in a co-endemic loiasis area of South-West Cameroon. Community-based directly observed treatment with 100mg doxycycline was administered to community members aged [≥]9 years. Wolbachia clearance at 6-months and treatment efficacy on microfilaridermia and palpable nodules were assessed at 30-months post treatment. Factors associated with reductions in microfilaridermia post treatment, including adherence to doxycycline treatment were assessed with mixed-effects logistic regression. Results Over 92% (2835/3080) of eligible participants took 35 days of 100mg doxycycline over 5 or 6 weeks. This regimen achieved a 62.8% microfilaridermia reduction and 99% palpable nodule reduction in the 720 participants included at follow-up. Wolbachia depletion was observed in 92% of skin samples at 6 months post treatment. The most important factor associated with microfilaridermia after 30 months was having missed at least 7 doxycycline consecutive doses (OR 3.11, 95%CI: 1.17-8.26). Incomplete treatment to a lesser extent was not associated with reduced efficacy at follow-up. Conclusion This large-scale community intervention shows that a 5-week treatment with 100mg doxycycline is feasible and has high curative efficacy against adult O. volvulus as measured by the dramatic reduction in the proportion of palpable nodules at 30-months post treatment. The high efficacy shows the tremendous potential of anti-Wolbachia drugs as part of the arsenal for onchocerciasis elimination and paves the way for the next generation of anti-Wolbachia drugs with shorter treatment courses, which will facilitate the implementation of alternative strategies to accelerate onchocerciasis elimination.
Kopeka, M. P.; Chiaborelli, M.; Sekhesa, P.; Sehrt, M.; Mohloanyane, T.; Ballouz, T.; Menges, D.; Brown, J. A.; Belus, J. M.; Gerber, F.; Raeber, F.; Williams, A.; Conserve, D. F.; Hyoky, M.; Hampanda, K.; Jackson-Perry, D.; Amstutz, A.; Hair SALON Expert Group,
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Introduction: The need to collaborate with community partners has long been considered essential for achieving sustainable HIV prevention and treatment. While the level of youth engagement in research varies by project, it is important that youth collaboration and partnership is meaningful and measurable. We previously conducted a survey that aimed to assess the acceptability of providing SRH/HIV services for young women at hair salons in Lesotho. The survey relied on participatory research with several community partners who were fundamental to its implementation. This study reports on the lessons learned from these participatory processes. Methods: The Hair SALON survey was conducted in Lesotho between December 2023 and August 2024. For the present study, we used the Report of Engagement in Community Research (REACH) tool to systematically define the various depths of engagement of stakeholders at different stages of the research. In addition, we conducted semi-structured individual interviews with the four young community partners who were involved as the Hair Salon Expert Group (HSEG) throughout the project, and a subset of six stylists who helped enroll clients to fill in the questionnaires. The audio-recorded interviews were transcribed, translated, and coded using thematic analysis. Results: Challenges to engagement with the research project included the lack of full understanding of the project team's expectations (for the HSEG), and difficulty engaging potential participants due to mistrust and the sensitive content of the project (for the stylists). As possible mitigation strategies, interviewees suggested developing better community dissemination efforts prior to the project start, and providing more training to the community partners. Facilitators for engagement included multiple altruistic, professional development, and material incentives. Conclusions: Our findings highlight that a participatory approach across all research phases is feasible and that various facilitators - beyond material incentives - motivate youth community partners to be part of such a project. However, some barriers remain. It is important to increase efforts to clarify community partners' roles and responsibilities beyond written agreements, which in turn improves their perceived ownership of the research.
Lareef, S.
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BackgroundLymphatic filariasis remains a public health concern in many endemic regions, where chronic disease persists despite substantial reductions in transmission. In Ghana, more than two decades of mass drug administration have significantly reduced disease prevalence and transmission; however, chronic manifestations and gaps in community understanding continue to be reported in parts of the north. This study assessed infection status, chronic morbidity burden, and community knowledge in a rural setting in northern Ghana approaching elimination. Methodology/Principal FindingsA community-based cross-sectional study was conducted in Birifor, northern Ghana, from October 2024 to January 2025. A total of 261 residents aged ten years and above were selected using random sampling. Data collection included structured questionnaires, clinical examination for chronic disease, and night blood microscopy for the detection of infection. No microfilariae were detected (0/261; 0%). However, chronic lymphoedema was identified in five individuals (1.9%), all aged over 40 years. Awareness of the disease was high (95.8%), yet only 39.5% of participants demonstrated good community knowledge and perceptions and self-reported preventive practices. Misconceptions regarding transmission, particularly beliefs that the disease is hereditary or caused by spiritual factors, were common. Participation in mass drug administration was high (93.1%). Despite this, chronic disease imposed a notable socioeconomic burden: all affected individuals reported loss of income, and 60% reported additional household income loss due to caregiving. Conclusions/SignificanceThese findings suggest that transmission in the study area is likely very low, although residual infection cannot be excluded; however, chronic disease and gaps in community knowledge persist. Strengthening morbidity management, improving community education, and providing support for affected households are essential. Sustained surveillance and integrated approaches will be critical to prevent resurgence and support long-term elimination efforts. Author SummaryLymphatic filariasis, also known as elephantiasis, is a mosquito-borne disease that can cause long-term swelling of the legs, arms, or genitals. Global efforts have greatly reduced its occurrence, especially through repeated mass drug administration to afflicted communities. However, many people continue to live with chronic swelling caused by past infections, which can affect their ability to work and participate fully in daily life. In this study, we examined the current situation of lymphatic filariasis in a rural community in northern Ghana that has received many years of treatment. We tested people for active infection, assessed signs of chronic disease, and explored what community members know and believe about the disease. We found no evidence of active infection, suggesting that transmission is now very low. However, some individuals were still living with chronic swelling and reported loss of income, while households also experienced financial strain due to caregiving. Although most people had heard of the disease, many did not fully understand how it is transmitted. Our findings show that reducing transmission alone is not enough. Continued education, community support, and access to care are needed to address the long-term impact of the disease and support ongoing elimination efforts.
Poyer, S.; Akiko Tangena, J.-A.; Mechan, F.; Worges, M.; Sternberg, E.; Koenker, H.; Fornadel, C.; Kilian, A.
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Background: The lifespan of insecticide-treated nets (ITNs) varies widely across settings, reflecting both intrinsic product characteristics and external factors related to use, care, and environment. While the resistance to damage (RD) score captures intrinsic product durability, there is no standardized metric to quantify contextual risks. This study presents a proof of concept for the Risk Index (RI), a composite measure of site-level risk factors for ITN physical durability and survival. Methods: We conducted a secondary analysis of durability monitoring data from 44 sites across 15 countries in sub-Saharan Africa, covering 14 ITN products. The RI was calculated as a weighted composite of 12 indicators spanning net handling, net care attitudes, and use environment. Associations between RI and median ITN survival were assessed using weighted linear regression and multivariable mixed-effects models adjusting for RD score, with country included as a random effect. Results: RI scores ranged from 25.1 to 83.7 across study sites. In bivariable analysis, a 10-point decrease in RI was associated with a 4.0-month increase in median ITN survival (95% CI: 1.7-6.3; p=0.001). In multivariable analysis adjusting for RD, this association remained significant but attenuated to 2.2 months (95% CI: 0.1-4.2; p=0.037). Independently, a 10-point increase in RD score was associated with a 3.5-month increase in survival (95% CI: 1.3-5.7; p=0.001). No interaction was observed between RI and RD. Predicted survival differed by approximately one year between the lowest- and highest-risk settings. Conclusion: The RI provides a standardized measure of contextual risk factors affecting ITN lifespan, independent of ITN product type. When used alongside a product's RD score, the RI enables improved interpretation of expected site-level variation in net performance. This combined framework offers a practical basis for incorporating behavioural and environmental risk into vector control planning and for tailoring ITN strategies to local conditions.
criscuolo, z.; Blanco, L.; Ferrara, F.; Ciaccio, K.; Gomez Carassale, L.; Gonzalez Reyes, M.; Machado Rivero, B.; Sosa Dias, F.; Facal Castro, J. A.
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Introduction: Hantavirus disease is an emerging and potentially severe zoonosis of global distribution. In Uruguay, it is transmitted by rodents inhabiting peridomestic, suburban, and rural areas. Global incidence is estimated at 150,000 to 200,000 cases per year, with up to 300 annual cases in the Americas. Since 1997, Uruguay's Ministry of Public Health (MPH) has monitored Hantavirus cardiopulmonary syndrome (HCPS), the most common clinical presentation in the region. By 2019, a total of 271 cases had been identified in the country, with an estimated mortality rate of nearly 50%. Objectives: To describe the clinical, epidemiological, and occupational characteristics of patients with Hantavirus disease in Uruguay during the pre-pandemic (2018-2019) and pandemic (2020-2021) periods. Methods: A descriptive, cross-sectional, observational study was conducted, including all serologically confirmed cases of Hantavirus infection reported to the MPH between 2018 and 2021. Clinical and demographic data were extracted from the mandatory reporting form for zoonotic diseases. Incidence and case fatality rates were calculated, and factors associated with fatal outcomes were analyzed. Results: A total of 58 confirmed cases were identified between 2018 and 2021. Most patients were male (62%), with a mean age of 36.5 years (SD 16). A decline in incidence was observed during 2020-2021, with no significant change in case fatality. Direct rodent exposure was the most frequently associated risk factor. Montevideo and Canelones were the most affected departments. Renal and pulmonary involvement were significantly associated with mortality. Conclusion: Hantavirus remains a relevant public health concern in Uruguay. Although a decrease in incidence was observed during the COVID-19 pandemic years, case fatality rates remained high. The findings underscore the need for sustained surveillance and early recognition, particularly in urbanizing regions.
Mahato, R. K.; Dahal, G.; Kandel, S.; Chaudhary, A.; Paudel, S. R.; Khaniya, R.; Shakya, P.; Devkota, B. P.; Sapkota, B. P.; Poudel, K. P.; Bajracharya, B.; Shrestha, D.; Jha, C. B.; Neupane, R.; Dhakal, K. B.; Bennani, K.
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BackgroundNepal has set a goal to eliminate lymphatic filariasis (LF) by 2030. As of 2024, Nepal has stopped the mass drug administration (MDA) in 56 of the 64 endemic districts and completed two rounds of MDA in six districts with persistent LF ([≥]2% antigen prevalence) using the three-drug regimen of Ivermectin, Diethylcarbamazine, and Albendazole (IDA), exceeding 65% coverage. We subsequently conducted an Epidemiological Monitoring Survey (EMS) to assess the impact of the MDA in reduction of LF infection prevalence below the transmission threshold and examine the factors associated with it. MethodsWe conducted a cross-sectional EMS nine months after MDA in 12 evaluation units (EUs) across six districts, with two sites per EU. We recruited a total of 7,343 individuals aged [≥]20 years, sampled using multi-stage sampling, ensuring at least 300 blood samples collected per site. We collected data on demographics and MDA participation. We performed the LF antigen testing for all participants, followed by night blood microfilariae testing in antigen-positive individuals. Statistical analyses included non-parametric tests, Chi-square and Fishers Exact tests, and multivariable logistic regression to assess outcomes after adjusting for potential confounders. ResultsNine of 12 evaluation units (EUs) recorded <1% microfilaremia, meeting the WHO threshold for passing EMS, while three EUs failed with [≥]1% prevalence in at least one site. Antigen and MF prevalence were 4.47% and 0.34%, respectively (ratio 13:1). Both Antigen and MF prevalences were significantly associated with female sex (AOR= 0.564, 95% CI: 0.441-0.721 and AOR = 0.326, 95% CI: 0.129-0.826 respectively) and participation in the most recent MDA round (AOR = 0.477; 95% CI: 0.385-0.591 and AOR = 0.089; 95% CI: 0.017-0.464 respectively). MDA uptake was influenced by age (<40 years, AOR = 0.72; 95% CI: 0.653- 0.793), sex (female, AOR = 1.438; 95% CI: 1.29-1.603), cross-border residence (AOR = 0.616; 95% CI: 0.558-0.681), and occupation (agriculture and housewife, AOR = 1.144; 95% CI: 1.008-1.298). MF prevalence was also associated with younger age (<40 years, AOR = 0.211; 95% CI: 0.071-0.626). ConclusionThe survey indicates progress toward LF elimination, with nine of twelve EUs achieving WHOs <1% microfilaremia threshold after two rounds of IDA-MDA. However, transmission persists in three sites, likely linked to poor MDA participation among specific subgroups-- particularly males, younger adults, and cross-border populations. Strengthening MDA coverage and compliance across all demographic and occupational groups, with special focus on border areas, is essential to achieve LF elimination in Nepal.
Nakiyingi, L.; Kikaire, B.; Nakayenga, S.; Kamulegeya, L.; Nakabugo, E.; Asio, J. N.; Bagaya, B.; Ssengooba, W.; Mayanja-Kizza, H.; Manabe, Y. C.
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Background: In sub-Saharan Africa where both tuberculosis (TB) and HIV are prevalent, empiric TB treatment in people living with HIV (PLHIV) persists due to limited sensitivity of sputum-based TB tests. We evaluated mortality among molecular test-negative presumptive TB adult PLHIV in a population where the majority are or have been on antiretroviral therapy (ART), comparing mortality between those who received empiric TB treatment and those who did not. Materials and Methods: From November 2017 to December 2020, Xpert-negative presumptive TB adult PLHIV were recruited at Mulago Referral Hospital and Kisenyi Health Centre-IV in Kampala, Uganda. Clinical data including TB symptoms, chest X-ray, and empiric TB treatment decision were collected. Laboratory investigations included CD4 cell count, serum cryptococcal antigen (CrAg), urine TB-lipoarabinomannan (TB-LAM), microbiological blood cultures, and sputum mycobacterial growth indicator tube (MGIT) cultures. Participants were followed monthly for 12 months to ascertain vital status. Results: Overall, 300 participants were enrolled; 61.3% inpatients, 55.7% female, median age 37 (IQR 29-45) years, 82.3% on ART, median CD4 206 cells/mm3 (IQR 36-507). Of the 300 participants, 68 (22.7%) received empiric TB treatment, of which 53 (77.9%) were inpatients. 12-month mortality was 31.0% (93/300); 91.4% among inpatients, 72% within three months post-enrolment. Mortality was higher among those who received empiric TB treatment (51.5 vs. 30.2 per 1,000 person-months; p=0.013) compared to those who did not. TB cultures were positive in 5.0% (15/300), of whom seven (46.7%) were also TB-LAM positive. CrAg was positive in 12.3% and 3.7% had positive blood culture. Conclusion: We found high mortality among Xpert-negative PLHIV, particularly those who received empiric TB treatment, despite high ART coverage. Cryptococcal antigenemia and bacteremia were not uncommon. In presence of negative Xpert results in PLHIV, clinicians should perform extensive laboratory evaluations to identify possible comorbidities or alternative non-TB diagnosis.
McCarthy, W. C.; Crain, C. J.; Olubodun, T.; George, I. A.; Birk, S. L.; Ekpo, U. F.; Mogaji, H.; Leng, H. T.; Kathiresan, R.; Salas, C.; Sekou, M. H.; Soneye, I.; Adeniyi, M. A.; Beaubrun, J.; Nwosu, K. O. S.; Oludolamu, A.; Kafil-Emiola, M.; Okesola, B. B.; Koether, P. J.; Simbassa, S. B.; Shah, N.; Ngai, M. K.; Oluwanifemi, O. B.; Efosa, I.; Hassan, A. E.; Fagbohun, V.; Oladokun, B. D.; Cannon, C.; Oncho, F.; Rehman, M.; Adeola, A.; Stella, A. J.; Abiodun, A.; Naimot, K.; Adeola, S. T.; Adelakun, O.; Copeland, T.; Amao, D.; Shokeen, V.; Kothari, A.; Tebo, K. K.; Lee, J.; Prakash, M.
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BackgroundUrogenital schistosomiasis is a major cause of preventable morbidity, primarily in rural, resource-limited regions. After decades of mass drug administration, changing epidemiologic landscapes, and ongoing resource limitations, test-and-treat models may be necessary to meet elimination goals. However, diagnostic capacity remains centralized and laboratory-dependent, and community-led, contextually adapted implementation strategies remain poorly defined. This study describes the accuracy and feasibility of a low-cost diagnostic toolkit and explores community-integrated implementation models. Methodology/Principal FindingsThis mixed-methods study enrolled 418 participants from five endemic sites near Oyan River Dam, Ogun State, Nigeria in July 2025. Urine samples underwent parallel analysis by community health extension workers utilizing the toolkit and by laboratory technicians using standard microscopy. The toolkit consisted of a reusable urine filtration device paired with a under-$2 paper microscope. Semi-structured interviews with community health extension workers and key informants were analyzed using the Consolidated Framework for Implementation Research. Prevalence was 27.5% (115/418). Community health extension workers demonstrated progressive improvement in diagnostic accuracy across five sequential communities (n=237), rising from 52.5% (95% CI 37.5-67.1) to 92.1% (79.2-97.3) over eight study days (Cochran-Armitage Z=3.08, p=0.002). Specificity improved from 53.6% to 96.3% (Z=3.00, p=0.003), final sensitivity reached 81.8% (52.3-94.9), and final Cohens kappa reached 0.803. In the hands of laboratory scientists, Foldscope microscopy achieved 91.0% sensitivity and 99.3% specificity. Conclusions/SignificanceCommunity-led diagnostic task-shifting for urogenital schistosomiasis control is accurate, feasible, and implementation-ready. Consolidated Framework for Implementation Research-guided analysis demonstrated strong end-user acceptability, with local ownership, collaboration, and trust-building as key implementation facilitators. This approach addresses diagnostic gaps in resource-limited endemic settings with relevance to other community health worker-led strategies. Author SummarySchistosomiasis is a parasitic infection that spreads through contact with freshwater and often goes undetected and untreated for years. Most common in sub-Saharan Africa, the disease damages the bladder and genitourinary tract, increasing risk of infertility, bladder cancer, and HIV transmission. It is most prevalent in rural communities where the snail intermediate host thrives in local water sources used daily for fishing, farming, and bathing. One such area is the Oyan River in Nigeria. Here, we found that barriers to diagnosis and treatment of the illness include distance and transportation. In this study, community health workers diagnosed their neighbors and community members using a low-cost toolkit: a <$2 / 2700 microscope, called the Foldscope paired with a small steel filter card we designed, called the SchistoFilter.. We enrolled 418 people across five villages along the Oyan River in Nigeria and trained eight community health workers to use this toolkit at the point of care. By the fifth community visite, they reached 92.1% accuracy. The study team interviewed community health workers and government officials to contextualize this approach, and they were enthusiastic: The tools can be used with confidence, the training is feasible, and what is most needed is a reliable supply chain and supportive oversight.