Tropical Medicine and Infectious Disease

Community engagement has emerged as a critical component in the effective control and elimination of neglected tropical diseases (NTDs), particularly in regions with persistent stigma and limited healthcare access. Drawing on case studies from Brazil, India, and Nigeria, this opinion piece explores how community-driven initiatives have successfully improved leprosy awareness, reduced stigma, and fostered early case detection and treatment adherence. The importance of culturally sensitive, inclusive approaches in health education and stigma reduction campaigns is highlighted, emphasizing the potential for community engagement to enhance national leprosy programs and contribute to the World Health Organization’s Zero Leprosy Strategy. By examining these examples, this article illustrates how integrating community participation into leprosy control and elimination programs can drive sustainable outcomes for achieving Zero Leprosy, even in resource-limited settings. Full article

To assess the burden of food-borne trematodiases in China from 1990 to 2021 and project the burden through 2035, data were captured from the Global Burden of Disease Study (GBD) 2021 datasets. The estimated prevalent food-borne trematodiase cases were 33.32 million (95% uncertainty interval (UI): 29.25–38.35 million) in China in 2021, contributing to 768,297.4 disability-adjusted life years (DALYs) (95% UI: 383,882.8–1,367,826.1). The number of prevalent cases and DALYs declined by 9.02% and 18.11%, and a downward decline was seen in age-standardized prevalence and DALY rates (estimated annual percentage change: −0.96% and −1.21%, respectively). A higher prevalence and DALY rates were observed among males than females, and the middle-aged group bore the highest burden, while the older population showed the most rapid increase in prevalent cases and DALY numbers. Projected DALY counts and rates remain stable through 2035 using the Bayesian age–period–cohort (BAPC) model. These findings demonstrate a decline in the burden of food-borne trematodiases in China from 1990 to 2021; however, the prevalence remained high, which contributed considerably to disability and premature death. Continued control efforts and targeted interventions are essential to further reducing the burden of food-borne trematodiases in China. Full article

Over the past 27 years, three major global TB control strategies have been implemented, and it is important at this stage to evaluate their impact on tuberculosis (TB) case notification rates (CNRs). This study, therefore, analyzed TB CNR trends from 1995 to 2022 across 208 countries and islands, using data from the WHO Global TB Programme database. Countries were classified by income level and population size based on World Bank criteria. The analysis revealed significant disparities in TB CNRs across income groups: Low-income, lower-middle-income, and upper-middle-income countries consistently reported higher CNRs compared to high-income countries. Regional analysis further demonstrated notable variations influenced by both economic and geographical factors. These findings reaffirm the strong link between TB and poverty, underscoring the need for a holistic approach to combat the disease. Efforts must extend beyond enhancing health care access and delivery to addressing the social determinants that drive TB transmission and progression. Full article

Schistosomiasis is caused by infection with trematode flukes of the genus Schistosoma. More than 700 million people worldwide are estimated to be susceptible to infection. In sub-Saharan Africa, schistosomiasis is the second most widespread neglected tropical disease after malaria. This retrospective investigation evaluated the incidence and impacts of schistosomiasis on communities across three major districts of the Eastern Cape province in South Africa using a cross-sectional retrospective observational analysis of secondary data from patients with microscopically confirmed schistosomiasis between 2019 and 2020. This study focused upon both rural and semi-urban areas, including Bizana, Butterworth, Centane, Elliotdale, Flagstaff, Idutywa, Lusikisiki, Libode, Mqanduli, Port St. Johns, Willowvale, and Mthatha. Data were obtained from three districts—Alfred Nzo, Amatole, and OR Tambo—covering both rural and semi-urban regions. This study included patients of all ages who submitted urine samples for schistosomiasis testing in the specified districts. A simple random sampling method was used to select 337 clinical records from the National Health Laboratory Service (NHLS) of Mthatha. Hospital records from the NHLS Microbiology Department of Mthatha were analyzed. St Barnabas Laboratory had the highest frequency of cases (34.1%), followed by Greenville Depot (17.8%) and Willowvale Laboratory (11.3%). Most cases were in the 10–19 age group (63.4%), followed by those under 10 years of age (24.9%). Male patients constituted 76.4% of the cases, while female patients accounted for 23.6%. Viable ova were observed in 98.2% of the samples. This study highlights a significant prevalence of schistosomiasis in the Eastern Cape province, with a higher incidence in rural areas and among males aged 10–19. These findings underscore the need for targeted public health interventions and continuous monitoring to control and prevent schistosomiasis in this region. Full article

Sickle cell disease (SCD) is a prevalent inherited blood disorder, particularly affecting populations in Africa. This review examined the disease’s burden, its diverse clinical presentations, and the challenges associated with its management in African settings. Africa bears a significant burden of SCD, with prevalence varying across countries and age groups. Newborn screening programs have highlighted the high prevalence of SCD at birth, emphasizing the need for early diagnosis and intervention. The clinical manifestations of SCD in Africa are multifaceted, encompassing acute complications like vaso-occlusive crises, acute chest syndrome, and stroke, as well as chronic complications such as organ damage and leg ulcers. Biological factors, including fetal hemoglobin levels, and demographic factors, like age and sex, influence disease severity and outcomes. The management of SCD in Africa faces numerous challenges. Limited access to resources, including diagnostic tools, medications, and trained healthcare professionals, hinders optimal care. The high cost of advanced therapies further restricts patient access. Cultural stigma and a lack of awareness create additional barriers to effective management. To address these challenges, early diagnosis through newborn screening programs and point-of-care testing is crucial. Comprehensive care models, including hydroxyurea therapy, pain management, and patient education, are essential for improving outcomes. Collaboration with international networks and leveraging local resources can enhance the sustainability of SCD programs. In conclusion, SCD significantly impacts African populations. Overcoming the challenges associated with its management requires addressing resource limitations, affordability issues, and cultural barriers. Early diagnosis, comprehensive care models, and ongoing research focused on affordability and accessibility are crucial for improving the lives of individuals living with SCD in Africa. Full article

Background: Studies of infective endocarditis (IE) are generally limited to institutions, underlining the need for more comprehensive epidemiological research. Objective: The aim of this study was to determine the mortality profile of IE-related deaths and related causes in Brazil at the national level and across regions. Method: We conducted a population-based study using data from the country’s mortality information system for the period 2000 to 2019. We identified IE-related deaths and related causes based on the ICD-10 codes. Cluster analysis was performed to determine the relationship between the variables. Results: There were 52,055 IE-related deaths during the study period. Deaths occurred predominantly among men and people aged between 60 and 79 years. The Southeast accounted for the largest proportion of deaths. The most frequent ICD-10 chapter mentioned in relation to IE-related deaths was diseases of the circulatory system. We identified three distinctive profiles: 1—an age of 80 years and over and women, where the most frequent chapters were endocrine, circulatory and metabolic diseases and the South and Southeast accounted for the largest proportion of deaths; 2—an age between 30 and 79 years and men, where the most frequent chapters were infectious and genitourinary diseases and the South and Southeast accounted for the largest proportion of deaths; and 3—an age between 0 and 29 years without any difference between sexes, where the most frequent chapter was diseases of the respiratory system and the North, Northeast and Midwest accounted for the largest proportion of deaths. Conclusions: The findings of the cluster analysis revealed distinctive IE-related mortality profiles, indicating regional differences. Full article

This study analyzed the trend and factors associated with medical–surgical complications in patients discharged from leprosy multidrug therapy at the Centre Hospitalier Régional Spécialisé (CHRS), in Macenta, Republic of Guinea. This was a retro 2012 (n = 54) and 2013 (n = 35) and then a slight decrease between 2014 (n = 34) and 2017 (n = 26). From 2019 (n = 18) to 2021 (n = 1), a significant d spective study using routine secondary data from 2012 to 2021. The most represented age group ranged from 25 to 59 years (73.8%), with a male predominance of 72.6%. Farmers represented 60.7% of the patients, 74.5% of the patients had plantar wounds, and 48.8% resided in the N’zerekore region. A trend analysis showed an overall significant decrease in the number of patients with complications between ecline was found. In the patients with leprosy reactions, there was a reduction in numbers from 48 in 2012 to 2 in 2014, with a predominance in men. There were significant associations between region, plantar perforation disease (p = 0.013), and physical disability (p = 0.029) and between year and leprosy reaction after the cure (p < 0.001). In summary, there was a high proportion of patients with plantar ulcers, which predominantly affected farmers, and a significant proportion with leprosy reactions and physical disabilities. Community awareness around leprosy and capacity building of the providers in terms of appropriate management may contribute to improving patients’ quality of life. Full article

Interactions between parasites and hosts are not fully understood, though the dynamic pattern of infection and reinfection in humans varies with different demographic variables and behavioral changes. A community-based non-equivalent control group post-test-only design, an aspect of quasi-experimental design (QED), was carried out between March 2019 and February 2020. For the extraction of data from respondents, structural questionnaires were filled. Their CD4 count and viral load from the database of the National Health Laboratory Services, Mthatha were recorded. The method applied for the identification of intestinal parasites was a direct examination of the stool and the use of concentration methods. The post-test analysis showed that the intervention sites that received THEdS (Treatment, Health education, and Sanitation) bundle had a cure proportion of 60% and a re-infection proportion of 40%. The post-test results on control sites (treatment-only group) showed that the cure proportion was 51.4% and the re-infection proportion was 48.6%. The viral load significantly reduced from 377 to 44 copies/mL with a significant increment in CD4 count from 244 to 573 (cells µL) and (p-value) = 0.002. The combination of THEdS is an effective measure to reduce infection and reinfection of intestinal parasites. The THEdS bundle is a sustainable control and prevention method for the control of helminthes and protozoan associated with unsanitary environment and poor personal hygiene among immune-compromised individuals like HIV/AIDS patients. Full article

Tuberculosis (TB) is a global health challenge associated with considerable levels of illness and mortality worldwide. The development of innovative therapeutic strategies is crucial to combat the rise of drug-resistant TB strains. DNA Gyrase A (GyrA) and serine/threonine protein kinase (PknB) are promising targets for new TB medications. This study employed techniques such as similarity searches, molecular docking analyses, machine learning (ML)-driven absolute binding-free energy calculations, and molecular dynamics (MD) simulations to find potential drug candidates. By combining ligand- and structure-based methods with ML principles and MD simulations, a novel strategy was proposed for identifying small molecules. Drugs with structural similarities to existing TB therapies were assessed for their binding affinity to GyrA and PknB through various docking approaches and ML-based predictions. A detailed analysis identified six promising compounds for each target, such as DB00199, DB01220, DB06827, DB11753, DB14631, and DB14703 for GyrA; and DB00547, DB00615, DB06827, DB14644, DB11753, and DB14703 for PknB. Notably, DB11753 and DB14703 show significant potential for both targets. Furthermore, MD simulations’ statistical metrics confirm the drug–target complexes’ stability, with MM-GBSA analyses underscoring their strong binding affinity, indicating their promise for TB treatment even though they were not initially designed for this disease. Full article

Marginalized groups in Manitoba, Canada, especially females and people who inject drugs, are overrepresented in new HIV diagnoses and disproportionately affected by HIV and structural disadvantages. Informed by syndemic theory, our aim was to understand people living with HIV’s (PLHIV) gendered and intersecting barriers and facilitators across the cascade of HIV care before and during the COVID-19 pandemic. This study was co-designed and co-led alongside people with lived experience and a research advisory committee. We employed semi-structured interviews with thirty-two participants and three questionnaires. Interviews were audio-recorded, transcribed, and coded, and descriptive statistics were performed on the first two questionnaires. Qualitative data analysis used thematic analysis and focused on identifying categories (individual, healthcare, and social/structural) related to the barriers and facilitators to HIV care. A total of 32 PLHIV completed this study and over 70% of females and 50% of males reported severe and moderate sexual abuse among other traumatic childhood experiences. Barriers to accessing or continuing in the cascade of HIV care included navigating the initial shock of receiving an HIV diagnosis, mental health challenges and inaccessible supports, substance use, violence (including intimate partner), internalized and enacted compounded stigma related to houselessness and substance use, discrimination by primary care service providers and social networks, lack of preventative and social supports, lack of accessible housing, and programmatic issues. COVID-19 increased mental health problems and disrupted relationships with HIV service providers and peers living with HIV. Facilitators to HIV care included stopping substance use, caring service providers particularly during HIV diagnosis, welcoming healthcare environments, social opportunities and integrated supports, and supportive social networks. Women, men, and non-binary PLHIV experience interconnected factors complicating their experiences with HIV care. Interventions should consider holistic, person-centered, and trauma-informed care options to address the barriers found in this research and appropriately serve PLHIV. Full article

The COVID-19 pandemic has underscored the pivotal role of vaccines in mitigating the devastating impact of the virus. In Thailand, the vaccination campaign against SARS-CoV-2 began on 28 February 2021, initially prioritizing healthcare professionals before expanding into a nationwide effort on 7 June 2021. This study employs a mathematical model of COVID-19 transmission with vaccination to analyze the impact of Thailand’s COVID-19 vaccination program from 1 March 2021 to 31 December 2022. We specifically assess the potential loss of lives and occurrence of severe infections across various age groups in a hypothetical scenario where vaccines were not administered. By fitting our model with officially reported COVID-19 death data, our analysis reveals that vaccination efforts prevented a total of 300,234 deaths (95% confidence interval: 295,938–304,349) and averted 1.60 million severe COVID-19 infections (95% confidence interval: 1.54–1.65 million). Notably, the elderly population over 80 years old benefited the most from vaccination, with an estimated 84,518 lives saved, constituting 4.28% of this age group. Furthermore, individuals aged between 70 and 74 years experienced the highest reduction in severe infections, with vaccination potentially preventing 8.35% of this age bracket from developing severe COVID-19. Full article

Leptospirosis is a widespread disease throughout the world, presenting in severe clinical forms in dogs. The pathogenicity of the different serovars in field infections is not fully documented, and clinical diagnosis is often limited to a combination of serological tests and molecular analyses. The latter, although a fundamental tool, cannot identify the infecting strain without further analysis. This study reports the use of various indirect (microscopic agglutination test, MAT) and direct (microbiological culture, real-time PCR) laboratory techniques, followed by typing protocols (Multi-locus Sequence Typing (MLST), Multiple Loci Variable number tandem repeat Analysis (MLVA), serotyping) that allowed for the identification of the Leptospira serovar Australis in a symptomatic and previously vaccinated dog (vaccine containing heterologous strains). This study reports long-term clinical follow-up (0–640 days) and describes the possible role of the infection in the development of chronic renal failure. This study aims to highlight how a combination of different techniques can be useful to better characterise the environmental circulation of zoonotic agents. Therefore, the identification and isolation of circulating L. strains would facilitate the updating of epidemiological data, enhance the knowledge of pathogenicity and long-term clinical effects, and provide a valuable resource for improving the efficacy of a specific serovar vaccination. Full article

Resistance to current antimalarial drugs is steadily increasing, and new drugs are required. Drug efficacy trials remain the gold standard to assess the effectiveness of a given drug. The World Health Organization (WHO)’s recommendation for the optimal duration of follow-up for assessing antimalarial efficacy is a minimum of 28 days. However, assessing antimalarial drug efficacy in highly endemic regions can be challenging due to the potential risks of acquiring a new infection in the follow-up period, and thus, it may underestimate the efficacy of the given drugs. A new treatment should be introduced if treatment failure rates exceed 10%. Overestimation occurs as a result of retaining a drug with a clinical efficacy of less than 90% with increases in morbidity and mortality, while underestimation may occur due to a misclassification of new infections as treatment failures with tremendous clinical and economic implications. Therefore, molecular genotyping is necessary to distinguish true new infections from treatment failures to ensure accuracy in determining antimalarial efficacy. There are three genetic markers that are commonly used in antimalarial efficiency trials to discriminate between treatment failures and new infections. These include merozoite surface protein 1 (msp-1), merozoite surface protein 2 (msp-2), and glutamate-rich protein (glurp). The genotyping of P. falciparum by nested polymerase chain reaction (n-PCR) targeting these markers is discussed with the inherent limitations and uncertainties associated with the PCR technique and limitations enforced by the parasite’s biology itself. Full article

Background/Objectives: Leptospirosis is a zoonotic disease that is widely distributed around the world and presents symptoms similar to other febrile illnesses in tropical regions, which complicates clinical diagnosis. This study aimed to evaluate the performance and agreement between serological diagnostic tests for detecting both acute and convalescent human leptospirosis, using the micro agglutination test (MAT) as a reference in an endemic region of the Colombian Caribbean. Methods: A prospective descriptive study was conducted on 275 participants with suspected leptospirosis. Paired serum samples were obtained, and an epidemiological survey was conducted. Using the MAT as the gold standard, we calculated positive and negative predictive values, sensitivity, specificity, and kappa index. A Bayesian latent class model was also used to compare the diagnostic tests. Results: In 223 paired serum samples, the sensitivity values for various stages of the disease ranged between 10.8% to 54.1% in the acute and 6.1% to 66.7% during the convalescent phase compared to the MAT. According to the Bayesian model, sensitivity was 9.5% to 75.3% in the acute phase and 5.7% to 85.3% in the convalescent phase. The Kappa value, an indicator of agreement, was moderate for the IgM ELISA in the acute phase (0.553) and substantial in the convalescent phase (0.692). Conclusions: The MAT was the best confirmatory test in both acute and convalescent phases of leptospirosis. Despite the high specificity of ELISA, 21.62% of participants identified as negative by IgM-ELISA in both phases were subsequently confirmed as positive by the MAT. It is necessary to re-evaluate diagnostic guidelines that do not employ the MAT for confirmation and to enhance the diagnostic and clinical identification of leptospirosis within healthcare institutions and public health laboratories while providing a rapid and reliable test for its implementation. Full article

Leptospirosis and hantavirus syndrome are two major rodent-borne diseases in Taiwan. Rocahepevirus ratii (RHEV), a virus closely related to hepatitis E virus (HEV, Paslahepevirus balayani), is emerging and has been reported to cause hepatitis in humans. We employed wastewater-based epidemiology to actively monitor rodent-borne pathogens, and the correlations with human cases were evaluated. Wastewater was collected using grab sampling at 11 sites along a sewer system including influents and effluents at a wastewater treatment plant in Tamsui, New Taipei City, Taiwan, monthly during June 2023 to May 2024. The presence of pathogens was examined by reverse transcription-polymerase chain reaction (RT-PCR). The result showed an overall positivity rate of 38.2% (50/131). Leptospira was detected most often (48/131, 36.6%), and RHEV and hantaviruses were found once each during the study period. Sequencing identified Leptospira interrogans close to isolates from rodents and human cases, while sequences of hantavirus and RHEV were most similar to isolates from rodents. No significant correlation was found with human cases or positive samples for rodent DNA. Here, we present an example of a One Health approach applying wastewater to environmental surveillance for the early detection and prevention of emerging diseases. Full article

Malaria prevention and control programs are mainly oriented to vector control, timely diagnosis and adequate treatment. Malaria transmission is influenced by several factors, including biological and social aspects. Thus, it is relevant to consider community beliefs and practices to ensure sustainable prevention and control strategies. This study aimed to determine knowledge, attitudes and practices (KAP) towards malaria in an endemic locality in northwestern Colombia. Preliminary data were collected through a focus group discussion. Subsequently, a KAP survey was administered to the community. KAP scores were associated with both sociodemographic characteristics and with previous malaria infection. Focus group data revealed knowledge gaps and the absence of or having worn-out nets. Survey results showed that participants recognized a mosquito bite as the transmission mode (72.09%), followed by dirty water (44.19%), high fever (86.05%) and headache (79.07%) as the main symptoms. Regarding attitudes, 44.19% of the people would go to the hospital in the case of having symptoms. The most recognized practices for disease prevention were the use of mosquito nets (65.12%) and fans (23.26%). The results showed that some people had misconceptions about the disease transmission mode. The analysis showed significant associations of either female gender and homemaker occupation with a good knowledge [OR = 3.74, (p = 0.04), OR = 3.55, (p = 0.04), respectively] or female with a positive attitude towards malaria control and prevention [OR = 4.80, (p = 0.04)]. These results showed that the identified gaps in KAP require increasing education among the community in addition to applying public health prevention efforts. The data may be useful in designing malaria control strategies that involve community participation. Full article

Pandemics of infectious disease and growing anti-microbial resistance (AMR) pose major threats to global health, trade, and security. Conflict and climate change compound and accelerate these threats. The One Health approach recognizes the interconnectedness of human, animal, and environmental health, but is grounded in the biomedical model, which reduces health to the absence of disease. Biomedical responses are insufficient to meet the challenges. The COVID-19 pandemic is the most recent example of the failure of this biomedical model to address global threats, the limitations of laboratory-based surveillance, and the exclusive focus on vaccination for disease control. This paper examines the current paradigm through the lens of polio and the global campaign to eradicate it, as well as other infectious threats including mpox and drug-resistant tuberculosis, particularly in the context of armed conflict. Decades before vaccines became widely available, public health measures—ventilation, chlorination, nutrition and sanitation— led to longer, healthier, and even taller lives. Chlorine, our primary tool of public health, conquered cholera and transformed infection control in hospitals. The World Health Organization (WHO), part of the One Health alliance, focuses mainly on antibiotics and vaccines to reduce deaths due to superbugs and largely ignores the critical role of chlorine to control water-borne diseases (including polio) and other infections. Moreover, the One Health approach ignores armed conflict. Contemporary wars are characterized by indiscriminate bombing of civilians, attacks targeting healthcare, mass displacement and lack of humanitarian access, conditions which drive polio outbreaks and incubate superbugs. We discuss the growing trend of attacks on healthcare and differentiate between types: community-driven attacks targeting vaccinators in regions like Pakistan, and state-sponsored attacks by governments such as those of Syria and Russia that weaponize healthcare to deliberately harm whole populations. Both fuel outbreaks of disease. These distinct motivations necessitate tailored responses, yet the WHO aggregates these attacks in a manner that hampers effective intervention. While antimicrobial resistance is predictable, the escalating pandemic is the consequence of our reliance on antibiotics and commitment to a biomedical model that now borders on pathological. Our analysis reveals the international indenture to the biomedical model as the basis of disease control is the root driver of AMR and vaccine-derived polio. The unique power of vaccines is reduced by vaccination-only strategy, and in fact breeds vaccine-derived polio. The non-specific effects of vaccines must be leveraged, and universal vaccination must be supplemented by international investment in water chlorination. This will reduce health costs and strengthen global health security. While vaccines are an important weapon to combat pandemics and AMR, they must be accompanied by the entire arsenal of public health interventions. Full article

Two-thirds of children with cerebral malaria (CM) exhibit retinopathy characterized by whitening, vessel color changes, and/or hemorrhages. The pathogenesis of malarial retinopathy is not fully understood. This study aimed to assess the relationship between malarial retinopathy and the severity of its components (macular whitening, retinal hemorrhages, and vessel color changes) with the total, circulating, or sequestered parasite load in children with CM. Total parasite burden was estimated by measuring plasma levels of Plasmodium falciparum histidine-rich protein 2 (PfHRP2), while the sequestered load was calculated as the difference between the total burden and circulating parasitemia. Children with retinopathy-positive CM (n = 172) had higher total and sequestered parasite burdens compared to retinopathy-negative children (n = 42) (both p = 0.049). In a subgroup with detailed retinopathy grading (n = 52), more extensive vessel color changes correlated with higher total, sequestered, and circulating parasite loads (p = 0.0057, p = 0.0068, and p = 0.0433, respectively). Peripheral retinal whitening was also associated with increased total and sequestered loads (p = 0.0017 and p = 0.0012). No association was found between retinal hemorrhages and parasite burden, indicating that other factors may influence their pathogenesis. Full article