Transactions of The Royal Society of Tropical Medicine and Hygiene最新文献

This study reports the detection of a relapsing fever Borrelia in the gilded boar tick, Dermacentor auratus, extracted from the ear canal of a human patient in Kedah, Peninsular Malaysia. Molecular analysis of the flaB gene identified the Borrelia species as identical to Borrelia sp. isolate HNF1F2 from China (ON060668) and closely related (99.60%) to Borrelia theileri isolate B22 from Colombia (ON135433). This article also provides a comprehensive review of human otoacariasis cases in Malaysia and discusses the limitations associated with these cases.

Background: In response to increasing primary resistance to isoniazid, the Brazilian Ministry of Health modified the tuberculosis (TB) treatment regimen at the end of 2009. The changes included adding ethambutol to the intensive phase, using fixed-dose combination tablets and adjusting isoniazid and pyrazinamide dosages. This study aimed to estimate the effect of the regimen change on all-cause mortality and, secondarily, on TB-specific mortality, treatment success and loss to follow-up.

Methods: We analysed cohorts of individuals ≥10 y of age who initiated TB treatment before (n = 145 528) and after (n = 161 264) the regimen change. Data were obtained from the national notifiable disease and mortality information systems. Missing data were imputed and effects were estimated using multilevel logistic regression models with states as the clustering level. Covariates were selected using a directed acyclic graph.

Results: The regimen change was not associated with all-cause mortality (relative risk [RR] 1.01 [95% confidence interval {CI} 0.98 to 1.04]) or TB-specific mortality (RR 0.98 [95% CI 0.95 to 1.02]). The treatment success rate was lower, and loss to follow-up was higher during the modified regimen period compared with the previous one. However, sensitivity analyses suggest that changes in the handling of transfers and missing outcome data may partly explain these findings.

Conclusion: We concluded that the modified regimen did not adversely affect survival among TB patients.

Background: A residual focus of bancroftian filariasis was found in Fuchuan County, Guangxi Zhuang Autonomous Region, China in 2007, and the response measures were implemented with participation and guidance from the National Institute of Parasitic Diseases at the Chinese Center for Disease Control and Prevention (China CDC). This study aims to assess the infection sources and summarize the management processes of the residual focus to fill the gap of the re-emergence of focus after elimination as a public health problem.

Methods: The assessment of the infection sources in the residual filariasis focus was conducted by on-site investigation and review of the database that was created and maintained by the China CDC. Historical records that were created by the China/Fuchuan CDC and maintained by the China CDC were retrospectively reviewed to summarize the experience of the handling process for filariasis. Statistical tests and logistic regression were performed to analyse the epidemic characteristics of the residual filariasis focus.

Results: A total of 7308 test records were reviewed, of which 919 were from the focus's natural village while 6389 were from other affected populations. Age and sex significantly affect filariasis infection, and the high-risk population was the 50-69 y age group and males in this focus. The on-site evaluation result and database monitoring showed that the focus did not spread locally or to neighbouring places and thus did not pose a public health threat. The emergency response process (ERP) for residual filariasis focus was developed and the rapid report and survey of the first case serves as the pre-trigger signal for ERP. Implementation of the ERP should account for local technical resource availability, representing the optimal approach under capacity-constrained conditions.

Conclusions: Maintenance of a sensitive and effective surveillance system and stockpiling of technologies and medicines are key to consolidating the elimination of filariasis and preventing its re-emergence. The disposal process is a systematic and scientific action that must follow epidemiological and medical principles according to local conditions.

Ghana aims to reduce malaria incidence by 50% and malaria mortality by 90% by 2028. The new R21 malaria vaccine aims to support achieving malaria-elimination goals, but it must be met with high population confidence and uptake. In this cross-sectional household survey in Karaga District, northern Ghana, 99.4% (n=175) agreed malaria is a serious disease to children, while 90.9% (n=160) agreed or strongly agreed they would like their children aged <5 y to take the new vaccine. Thus, in these communities, the highly effective vaccine can plausibly expect to have high rates of uptake, contributing to Ghana's efforts to improve health outcomes.

Background: Zika virus (ZIKV) is a mosquito-borne flavivirus mainly transmitted by Aedes aegypti and Aedes albopictus. While well-studied in the Americas, data from Southeast Asia, especially Myanmar, remain limited. This study assessed ZIKV infection among dengue-suspected patients in Yangon, Myanmar, from 2017 to 2019.

Methods: This was a cross-sectional retrospective study that collected serum samples from 1162 clinically dengue-suspected patients. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to detect ZIKV RNA and serological assays were used to identify ZIKV-specific immunoglobulin M (IgM), IgG and neutralizing antibodies. The age, gender, clinical manifestations and coinfections with dengue virus (DENV) were determined.

Results: Of the 1162 samples, 23 (2.0%) were positive for ZIKV by RT-qPCR. Among these, nine samples showed coinfection with DENV: four with DENV-1, two with DENV-3 and three with DENV-4. Of the 111 (9.6%) samples that tested positive for ZIKV IgM, 11 (9.9%) had neutralizing antibodies against ZIKV, with 9 (8.1%) confirmed as ZIKV positive and 2 (1.8%) classified as probable cases.

Conclusions: Our study reported that 32 cases (2.8%) were confirmed as ZIKV infections by molecular and serological detection. The findings underscore the need for improved surveillance, diagnostic accuracy and public health interventions to mitigate the impact of ZIKV.

Background: This study examined whether Onchocerca ochengi infection can influence physiological and behavioral changes related to epilepsy using a BALB/c mouse model.

Methods: Male and female mice (4-6 weeks old) were surgically implanted with O. ochengi worm masses or underwent sham operations as controls. Body and organ weights were recorded, and worm viability was evaluated using the MTT assay. Behavioral tests assessing anxiety, memory, and muscle tone were performed on days 63-66 and 121-124 post-implantation.

Results: Infected mice exhibited lower body weights (P=0.0031) and heightened anxiety-like behavior at day 63 (increased grooming, P=0.0058) that declined by day 121 (P=0.0541). Memory deficits were observed initially (Y-maze, P=0.0065) but resolved later (P=0.8100). Muscle strength increased at day 63 (P=0.0043) with no differences by day 121 (P = 0.2468). All retrieved worms were nonviable.

Conclusions: O. ochengi infection induced transient behavioral and physiological alterations in mice, including early anxiety and memory impairment resembling features of onchocerciasis-associated epilepsy. These findings support a mechanistic link between filarial infection and neurological dysfunction, validating this model for future pathophysiological studies.

Plain language summary: This study explored how Onchocerca ochengi, a parasite, affects brain function and behavior in mice, as a way to understand epilepsy linked to parasitic infections in humans. The infected mice showed weight loss, anxiety-like behavior and memory problems early on, which later improved over time. These findings may help explain how parasitic infections can contribute to neurological conditions like epilepsy.

This article evaluates the outcomes and insights from a collaborative initiative between Moorfields Eye Hospital volunteers, Eye Health Africa and the Ubora Foundation Africa focused on strengthening ophthalmic services in Uganda, particularly at Hoima Regional Referral Hospital. Drawing on comparative insights from National Health Service facilities in the West Midlands (UK), the article reflects on infrastructure limitations; workforce constraints; the collaborative, system-level interventions that must be introduced; and some initial initiatives made possible through the exchange. Emphasis is placed on sustainability, local capacity building and bilateral learning, with implications for replicable models of ophthalmic care development in low-resource settings. Lessons learned reveal the importance of cultural humility, context-specific innovation and long-term investment in human resources for health in the global fight against avoidable blindness and improving patient outcomes while offering a framework for future global eye health partnerships.

In the Kpone-Katamanso Municipality (Greater Accra, Ghana), as part of enhanced surveillance, health teams assessed the cross-sectional prevalence of schistosomiasis and soil-transmitted helminths (STHs), both neglected tropical diseases (NTDs) in school children. Across 527 participants ages 7-19 y, the STH prevalence was 4.9% and schistosomiasis prevalence was 4.7%. There was a significant association with being male (p=0.002), being a resident in Zenu (p=0.049) and swimming at the nearby dam (p≤0.001). This is a lower prevalence than has been previously reported, so potentially this is evidence that sustained long-term NTD control efforts are having an impact in this municipality.

Chagas disease is a parasitic infection caused by Trypanosoma cruzi. Although the host immune response has been extensively studied, important knowledge gaps remain, particularly regarding the complex and multifaceted immune evasion mechanisms employed by the parasite, both at the innate and adaptive levels. In recent years, multiple promising vaccine candidates have been developed, but further evaluation is needed across the different phases of clinical trials. Therefore, the aim of this review is to examine the host immune response to T. cruzi, the parasite's immune evasion strategies and recent advances in vaccine development aimed at controlling infection.

Background: Malaria is a serious public health issue in Pakistan. This study investigated the spatiotemporal patterns, seasonal dynamics, and molecular confirmation of malaria in District Malakand, Khyber Pakhtunkhwa, from 2011 to 2017.

Methods: Clinical data were collected from the District Headquarters Hospital over 7 y. A random sample of 120 patients from 2017 was used for microscopic and molecular identification. Spatial-temporal patterns were analysed using ArcGIS (Environmental Systems Research Institute (Esri), Redlands, California, United States). Statistical analyses were performed using SPSS (IBM Corporation, Armonk, New York, United States) and R software (R Foundation for Statistical Computing, Vienna, Austria).

Results: Of 41 863 tests, 6246 were positive, yielding an overall test positivity rate of 14.92%. Males (58.89%) were more affected than females. The highest proportion of cases was in the 1-20-y age group. The annual test positive rate declined from 32.97% in 2011 to 10.77% in 2017. Seasonally, autumn had the highest case proportion (46.73%); winter the lowest (7.09%). Spatial analysis identified Gharhi, Dargai and Haryankot as high-burden areas. Inverse distance weighting highlighted these as hotspots for potential transmission. PCR confirmed microscopy-based species identification.

Conclusions: Malaria in Malakand peaks in autumn, affecting males and individuals aged <20 y most. Neighbouring villages are at risk from hyper-endemic areas. Microscopy remains a dependable diagnostic tool here.