Tropical Medicine and Health最新文献

Background: Opisthorchiasis caused by Opisthorchis viverrini infection is a major public health concern in Thailand. Despite decades of surveillance and control efforts, accurately estimating the true prevalence of O. viverrini remains a challenge. This study aimed to investigate the epidemiology of O. viverrini infection in an endemic community in northeastern Thailand using a combination of microscopic and molecular diagnostic methods.

Methods: A cross-sectional survey was conducted from May to July 2025 in Kusuman District, Sakon Nakhon Province. Demographic and behavioral data were collected using a standardized questionnaire. Stool samples were obtained from participants and examined using simple wet smear and modified Kato-Katz techniques to detect O. viverrini eggs and other intestinal parasites. In parallel, DNA was extracted from stool samples and polymerase chain reaction (PCR) targeting the internal transcribed spacer 2 (ITS2) gene was performed to confirm the presence of O. viverrini. Multiple logistic regression was used to investigate factors associated with infection.

Results: Among 246 participants, stool microscopy detected intestinal helminth infections in 10.2%, with O. viverrini being the most prevalent species (6.1%). Notably, all microscopy-positive O. viverrini cases were very light-intensity infections (< 500 eggs per gram [EPG] of stool). ITS2-specific PCR identified a higher prevalence of O. viverrini infection at 19.9%, detecting significantly more than three times as many cases as microscopy (P < 0.001). Multivariate regression analysis further showed that being male was associated with higher odds of O. viverrini infection (adjusted odds ratio [aOR] 5.55; 95% CI 2.41-12.83; P < 0.001), whereas participants aged 41-60 years had significantly lower odds compared to older individuals (aOR 0.08; 95% CI 0.03-0.19; P < 0.001).

Conclusions: This study demonstrates that O. viverrini infection remains highly prevalent in rural communities of northeast Thailand. Molecular diagnosis was more sensitive than conventional microscopy and key demographic risk factors were identified. These findings underscore the need for active surveillance and provide valuable data to guide and strengthen future prevention and control strategies for O. viverrini and other helminth infections in the region.

Background: Border surveillance measures, including health screening and mandatory quarantine for travelers, are critical components of global pandemic response strategies. In Lao PDR, however, no known study has assessed the performance of the quarantine system, which was designed to protect the health of both citizens and incoming travelers, particularly during the COVID-19 pandemic and in preparation for future outbreaks. This study therefore evaluates adherence to the national COVID-19 quarantine protocols at two ground crossings (Vietnam-Laos and Thailand-Laos) in Savannakhet Province during the COVID-19 pandemic.

Methods: A retrospective cross-sectional study was conducted among 380 registered adult incoming travelers who entered Lao PDR via Dansavanh-Lao Bao border or Second Thai-Lao Friendship Bridge between April 2020 and March 2021. Data were extracted from point-of-entry registers, provincial hospital records, and quarantine facility registers. Overall quarantine performance (OQP) was defined as completion of the Lao PDR national quarantine protocol. Binary logistic regression was employed to identify the factors associated with OQP completion.

Results: Of the 380 incoming travelers, 277 (72.9%; 95%CI 68.2-77.1) completed the full quarantine procedures. Body temperature screening was conducted for 348 individuals (91.6%), with 13 (3.7%) presenting with fever ≥ 37.5 °C and referred for further screening. Among 335 incoming travelers directed to quarantine facilities, 264 (78.8%) completed the 14-day quarantine. Multivariate analysis revealed that female incoming travelers were significantly more likely to complete quarantine procedure than males (aOR: 1.84; 95%CI 1.14-2.96; p = 0.013). Those who traveled into the provinces other than Savannakhet had higher odds of quarantine completion (aOR: 1.78; 95%CI 1.49-3.26; p = 0.042).

Conclusion: Based on locally defined indicators, the quarantine system achieved OQP rate of 72.9% which reflects an acceptable level of compliance. Gender and destination province were significant predictors of adherence. Enhancing communication strategies and standardizing strict quarantine procedures could improve border surveillance and preparedness for future public health emergencies.

Background: Malaria remains a leading cause of morbidity among children under five in Ghana despite widespread deployment of insecticide-treated nets (ITNs). Understanding the effectiveness of ITN use under routine programmatic conditions is essential for guiding national malaria control strategies. This study assessed the impact of ITN use on malaria infection among children under five and explored contextual factors that may influence intervention performance.

Methods: We analyzed nationally representative, georeferenced data from surveys in Ghana. Spatial quantile maps were created to describe regional patterns of ITN ownership, ITN use, indoor residual spraying (IRS), and malaria prevalence. Multilevel regression models, estimated using conventional and Bayesian approaches, examined the association between ITN use and malaria infection while accounting for enumeration area and regional clustering. Inverse probability of treatment weighting (IPTW) based on propensity scores was used to balance covariates, and the marginal odds of ITN use were estimated. We further estimated the risk difference (RD) using a linear probability model.

Results: This study included a total of 11,481 children. Sleeping under an ITN led to an estimated 13% reduction in the odds of malaria infection (aOR = 0.87; 95% CI 0.81-0.93) and an absolute risk reduction of 2.2% (RD = - 0.022; 95% CI - 0.037 to - 0.006). Spatial analyses revealed misalignment between intervention coverage and malaria burden, while behavioral and contextual factors likely contributed to the modest effect size.

Conclusions: ITN use provides meaningful but limited protection against malaria infection among young children in Ghana. Strengthening malaria control will require attention to behavioral and contextual drivers of exposure and improved alignment of interventions with local transmission patterns.

Background: Amebiasis, caused by Entamoeba histolytica, has emerged as a sexually transmitted enteric infection among men who have sex with men (MSM) and people with HIV (PWH) in developed countries. While previous surveillance studies in Taiwan among PWH showed ongoing transmission, investigation on E. histolytica infection among non-HIV MSM using newer diagnostic methods and ELISA-IgG seroprevalence surveys is lacking.

Methods: From March 2024 to February 2025, we conducted a cross-sectional study during an LGBTQ + Pride event and at a tertiary medical center in southern Taiwan. MSM participants were recruited during anonymous HIV and syphilis testing, or during follow-up visits for HIV pre-exposure prophylaxis or antiretroviral therapy. We collected serum samples for E. histolytica ELISA IgG and self-collected rectal swabs for molecular diagnosis. DNA extraction was performed using an optimized protocol. A novel quantitative PCR assay utilizing specific primers and a double-quencher probe was developed to enhance detection specificity and reduce background noise.

Results: Among 139 non-HIV MSM participants, 11 individuals tested positive for E. histolytica IgG, yielding a seroprevalence of 7.9%. Molecular testing by rectal swab quantitative PCR identified two positive cases (1.4%). Of the two positive cases, one developed diarrhea just before examination, while the other remained asymptomatic. The novel PCR primer probe set detected E. histolytica DNA from rectal swab samples with high specificity.

Conclusions: The present study investigated E. histolytica infection among non-HIV MSM in Taiwan using ELISA IgG and novel molecular diagnostic methods. The seroprevalence of 7.9% suggests ongoing transmission in this population. The optimized self-collected rectal swab protocol combined with the novel PCR assay provides a practical surveillance tool. Further investigation and targeted prevention strategies are warranted.

Background: Prostate cancer in Africa is a significant public health problem with a consistently increasing high mortality rate. The World Health Organization (WHO) estimates that 80% of the population in Africa uses herbal medicines. However, research on the cytotoxicity related to African plant extracts against prostate cancer is still limited, which retards the development of potential anticancer agents from these plants. This review compiles data on the cytotoxicity of African medicinal plants used in the management of prostate cancer.

Methods: A systematic literature review search was conducted from January 2015 to June 2025 on studies on the cytotoxic activity of medicinal plants used in the management of prostate cancer in Africa. The review was based on the Preferred Reporting Items for the Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The study considered cytotoxic studies available on the search engines of ScienceDirect, Google scholar, Web of Science, SpringerLink, Scopus, PubMed, BioMed, and Scientific Electronic Library Online (SciELO). The data were analysed using SPSS statistical software.

Results: Twenty-eight articles on cytotoxic activity of anti-prostate cancer medicinal plants in Africa were evaluated. The studies reported 45 medicinal plants with cytotoxic activity against prostate cancer cell lines. The extract of Dichrostachys cinerea with IC₅₀ of 8.04 μg/ml on 22RV1 exhibited the strongest cytotoxic activity. This was followed by extracts of Acacia gerrardii with IC₅₀ of 10.45 μg/ml on DU-145, Ormenis eriolepis with IC₅₀ of 19.31 μg/ml on LNCaP, and Momordica charantia with IC₅₀ of 20.39 μg/ml on PC3. The cytotoxic activity of the medicinal plants is attributed to the presence of phytochemicals acting either singly or synergistically, causing cancer cell apoptosis, cell cycle arrest, inhibition of androgen receptors and inhibition of reactive oxygen species/free radicals.

Conclusion: The investigated medicinal plants contain bioactive compounds that exhibited cytotoxic activity against prostate cancer cell lines. The bioactive compounds found in these plants could be used in clinical trials in the development of prostate cancer therapies.

Background: Dengue is an arboviral disease transmitted by Aedes aegypti and Aedes albopictus mosquitoes. Natural plant-based insecticides are promising alternatives to chemical insecticides but face challenges, including rapid degradation of bioactive compounds in aquatic environments. In this study, bioactive plant extracts were encapsulated in water-insoluble CaCO₃ submicron carriers, which are of great interest as targeted drug delivery systems due to their bioadhesive, biocompatible properties, and eco-friendly nature. This approach was applied to achieve the highest efficiency with controlled release of bioactive compounds targeting dengue mosquito larvae.

Methods: CaCO₃ submicron particles were synthesized using a mixture of Ca(CH₃COO)₂ and NaHCO₃ in H₂O and diethylene glycol as solvents. The combined plant extract of Capsicum frutescens (Naimiris) and Allium sativum (garlic), which showed significant larvicidal activity against dengue mosquito larvae, was encapsulated into CaCO₃ particles, and their release properties and larvicidal activity were examined. The results of the SEM, XRD, XRF, and FTIR analyses confirmed the morphology, structure, and chemical characterization of the CaCO₃ submicron particles. Qualitative phytochemical analysis was also conducted, and the total phenolic and total flavonoid contents were investigated quantitatively.

Results: The diameter of CaCO₃ particles was 252.3-676.4 nm, and the average size was 419.7 nm. 85.56 ± 4.65% of plant extract was encapsulated into CaCO₃ particles, and about 27% of the encapsulated product was released to the medium up to 10 days. Larvicidal activity showed concentration and time-dependent mortality in mosquito larvae, resulting in up to 55% mortality after 10 days for the highest concentration tested.

Conclusion: The results confirmed that CaCO₃ submicron carriers are effective as slow-release drug delivery systems.

Background: This study explored the role of myocardial injury in the prognostic assessment of severe fever with thrombocytopenia syndrome (SFTS) and hemorrhagic fever with renal syndrome (HFRS) patients, and analyzed its risk factors.

Methods: A retrospective study included 188 SFTS and 101 HFRS patients (2020-2024) from two hospitals. Epidemiological, clinical, and laboratory data were dynamically recorded and statistically analyzed.

Results: SFTS patients were older (65.35 ± 11.04 vs. 53.26 ± 14.66 years) and had more females (56.90% vs. 26.70%, both P < 0.001). HFRS was more likely to present early symptoms (myalgia, fatigue/anorexia, abdominal pain, diarrhea, vomiting, skin petechiae/ecchymosis, headache; all P ≤ 0.040). SFTS mortality (19.70%, 37/188) was significantly higher than HFRS (4.00%, 4/101, P < 0.001). Both groups had elevated myocardial markers (ALT, AST, CK, CK-MB, cTn, LDH, α-HBDH): HFRS had higher levels during days 3-7 (which then decreased), while SFTS levels increased and exceeded those of HFRS during days 8-14. SFTS patients with myocardial injury had higher mortality (29.10% vs. 11.80%, P = 0.003), but HFRS showed no mortality difference between those with and without myocardial injury (P = 0.952). Myocardial injury risk factors emerged in both groups during days 3-7, increased during days 8-14, peaking on day 10 (SFTS) and days 6/12/13 (HFRS).

Conclusion: SFTS has a higher mortality rate. Myocardial injury is common and early in both groups: HFRS patients show rapid recovery, while SFTS patients experience worsening injury associated with death. Early intervention targeting risk factors is key to reducing mortality.

Introduction: The COVID-19 pandemic has significantly impacted disease burdens, yet updated nocturia epidemiological data remain limited. This study characterized age-sex-race disparities in nocturia prevalence and evaluated pandemic-related temporal changes.

Methods: Using NHANES data (2017-2023), this cross-sectional study included 10,946 adults (≥ 20 years). Primary outcomes were nocturia prevalence (≥ 1 and ≥ 2 nightly episodes). Analyses incorporated sampling weights and multivariable logistic regression.

Results: Overall weighted prevalence reached 71.9% for nocturia (≥ 1 time/night) and 31.2% for clinical nocturia (≥ 2 times/night). Post-pandemic surge was significant: nocturia increased from 70.0% to 75.3% (P = 0.002) and clinical nocturia from 28.5 to 36.0% (P < 0.001) (2017-2020 vs. 2021-2023). Young males showed the steepest clinical nocturia escalation (11.6-24.1%, P = 0.001), while middle-aged females experienced significant increases in overall nocturia (70.2-77.1%, P = 0.054). Racial disparities widened post-pandemic, with Hispanic populations demonstrating a 43.5% increase in clinical nocturia (26.9-38.6%, P < 0.001). Multivariable regression confirmed obesity as an independent risk factor (OR = 1.312, 95% CI 1.119-1.539, P = 0.002). Obesity-related exacerbation intensified during the pandemic: obese males experienced a 38.9% surge in nocturia (54.5-75.7%, P = 0.005) and 201% increase in clinical nocturia (10.4-31.3%, P = 0.007).

Conclusions: Nocturia prevalence escalated markedly post-pandemic, disproportionately affecting young and obese males. Targeted interventions addressing metabolic health and socioeconomic disparities are urgently needed.

Background: Smoking is a key modifiable risk factor for rheumatoid arthritis (RA). This study aimed to assess the global burden of RA attributable to smoking and analyze its spatiotemporal trends from 1990 to 2021, with forecasts to 2050.

Methods: Using data from the Global Burden of Disease Study 2021, we extracted deaths, disability-adjusted life years (DALYs), and age-standardized rates (ASRs) for RA attributable to smoking across 204 countries and regions. Analyses were stratified by age, sex, socio-demographic index (SDI), and region. Temporal trends were assessed using estimated annual percentage change (EAPC), and future burden was projected using ARIMA models.

Results: From 1990 to 2021, global deaths and DALYs due to RA attributable to smoking increased by 26.3% and 48.1%, respectively, reaching 2,264 deaths (95% UI: 1509-2911) and 215,780 DALYs (95% UI: 147,153-300,761) in 2021. However, the corresponding ASRs declined, with ASDR falling from 0.05 to 0.03 per 100,000 and ASRDALYs from 3.44 to 2.48 per 100,000. The burden was higher among males, the elderly, and middle-to-high SDI regions. Males had 2.42 times more deaths and 1.68 times more DALYs than females. Forecasts indicate continued increases in absolute deaths and DALYs through 2050, despite declining ASRs.

Conclusion: The global burden of RA attributable to smoking remains substantial and is projected to grow. Targeted tobacco control and public health strategies are urgently needed to mitigate this preventable cause of RA.

Snakebite envenoming represents a significant public health challenge, particularly in regions, where venomous snakes are endemic. The One Health approach, which recognizes the interconnectedness of human, animal, and environmental health, offers a promising framework for addressing the complex dynamics of snakebite envenoming. This review provides a comprehensive epidemiological analysis on the role of One Health in snakebite prevention, control and research efforts. Drawing on interdisciplinary perspectives, we examined the aspects on environmental, social, and economic factors influencing snakebite incidence, as well as the interactions between humans, snakes, and domestic animals. We also highlighted innovative strategies for integrating One Health principles into snakebite surveillance, education, and treatment initiatives. By synthesizing current knowledge and identifying key research gaps, this paper aims to inform the strategic efforts to mitigate the burden of snakebite envenoming within a holistic and collaborative framework.