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

Globally, snakebites cause an estimated 80 000-140 000 deaths annually. While there are evidence-based recommendations for managing snakebite victims, recommendations on the prevention of snakebites are limited to expert opinions. We conducted a rapid review to summarise evidence from human studies with a control group on preventing snakebites. Searching PubMed, Web of Science, Scopus, CINAHL and EMBASE with inclusive search terms without language or time limits only yielded three eligible studies (one case control study and two prospective controlled clinical studies), highlighting a knowledge gap. Two studies in Nepal by the same group showed that health education of stakeholders and sleeping under a bednet can significantly reduce snakebite incidence (p<0.05), but these observations are not confirmed elsewhere, and because of the high risk of bias the certainty of evidence was low. The third study from Sri Lanka, which assessed if sleeping above ground would prevent snakebites, had inconclusive results. This demonstrates an urgent need for studies with a control group to guide evidence-based recommendations for snakebite prevention. Potential interventions tested can range from low-cost measures such as wearing appropriate footwear in resource-limited settings to testing the efficacy of chemical, biological (e.g. rodent control) or device-based methods and community-supported platforms tracking snakebite sightings with real-time geolocation data in highly resourced settings.

The 'One Health' (OH) approach is the most promising idea in realising the global goal of eliminating canine-mediated human rabies by 2030. However, taking an OH approach to rabies elimination can mean many different things to different people. We conducted a systematic review scrutinizing economic evaluations (EEs) retrieved from MEDLINE OVID, Embase OVID, Global Health OVID, CINAHL EBSCO and ECONLIT EBSCO that used the OH approach with the intent of identifying cost-effective sets of interventions that can be combined to implement an optimal OH-based rabies elimination program and highlight key gaps in the knowledge base. Our review suggests that an optimal OH program to tackle rabies should incorporate mass dog vaccination and integrated bite case management in combination with efficient use of post-exposure prophylaxis along with a shift to a 1-week abbreviated intradermal rabies vaccine regimen in humans. We recommend that future EEs of OH interventions for rabies elimination should be performed alongside implementation research to ensure proposed interventions are feasible and adopt a wider societal perspective taking into account costs and outcomes across both the human health and animal welfare sectors. The systematic review has been registered with PROSPERO.

Background: Cutaneous leishmaniasis (CL), an emerging vector-borne ailment in Khyber Pakhtunkhwa (KPK), Pakistan, exhibits diverse spread patterns and outbreaks.

Methods: To comprehend its epidemiology and identify parasite species, we conducted an active survey on suspected CL cases (n=8845) in KPK.

Results: Microscopy and internal transcribed spacer-1 PCR-restriction fragment length polymorphism (RFLP) molecular techniques detected Leishmania spp. in blood samples. Phylogenetic analysis gauged genetic affinities with other areas. District Bannu displayed the highest CL impact (14.58%), while Swat had the lowest impact (4.33%) among cases. Annual blood examination rate, parasite incidence and slide positivity rate were 4.96 per 1000 people, 0.0233 and 0.047%, respectively. CL infections were prevalent in 1- to 20-y-olds, with males (57.17%) more vulnerable than females (42.82%). Single lesions occurred in 43.73% of patients, while 31.2% people had two lesions, 17.31% had three lesions and 7.74% had more than three lesions. Most had sand-fly exposure but lacked preventive measures like repellents and bed nets. Leishmania tropica was confirmed via RFLP analysis in amplified samples. Phylogenetic analysis unveiled genetic parallels between L. tropica of KPK and isolates from China, Iran, Afghanistan, India, Syria and Morocco.

Conclusions: Urgent comprehensive control measures are imperative. Early detection, targeted interventions and raising awareness of CL and sand-fly vectors are vital for reducing the disease's impact. International collaboration and monitoring are crucial to tackle Leishmania spp.'s genetic diversity and curtail its cross-border spread.

Background: Hepatitis B virus (HBV) infection is a worldwide public health burden, especially in Asia and Africa. Concerns were raised that foetal exposure to HBV and antiretroviral therapy (ART) might suppress the innate immune response and reduce the production of hepatitis B surface antibody (HBsAb) in foetuses and infants. We therefore conducted the current study to evaluate the impact of ART on the development of the immune response to HBV in foetuses and infants.

Methods: We selected lamivudine instead of telbivudine or tenofovir as the intervention measurement because it was the oldest and most widely used ART during pregnancy and its safety data have been sufficiently documented. A comprehensive search was conducted in eight electronic databases, including four Chinese and four English databases. Studies that met the following eligibility criteria were included: human randomized controlled trials (RCTs); participants in the treatment group were exclusively exposed to lamivudine; participants in the control group were exposed to placebo, no treatment or hepatitis B immunoglobulin; all participants were HBV-positive pregnant women with a high viral load and the main outcome of interest was neonatal HBsAb seropositivity. Data were tabulated and analysed using R software.

Results: Nine RCTs were included and analysed. Compared with controls, lamivudine significantly decreased HBsAb seronegativity in the newborn within 24 h after birth (indicating the foetal immune response to HBV). Similar results were noted in infants within 6-7 months after birth and infants within 12 months (indicating the neonatal immune response to HBV vaccine).

Conclusions: Lamivudine treatment in late pregnancy boosted the foetal immune response to HBV in utero and enhanced the neonatal immune response to hepatitis B vaccine after birth.

Background: Microsporidia and Cryptosporidium are obligate intracellular protozoa. These medically important species are recognized as opportunistic organisms in intestinal complications in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome patients.

Methods: The current cross-sectional study was designed and conducted from August 2016 to August 2017 to determine intestinal Cryptosporidium and microsporidia spp. in HIV-infected individuals from the Behavioral Diseases Counseling Center, Tabriz, Iran, by modified acid-fast and modified trichrome staining and nested polymerase chain reaction (PCR) and real-time PCR.

Results: Of 100 HIV-infected persons, 21.0% (95% confidence interval [CI] 13.0 to 30.0) and 18.0% (95% CI 11.0 to 26.0) were identified as Cryptosporidium and microsporidia, respectively, by the microscopic method. Of these 100 HIV-infected persons, 18.0% (95% CI 11.0 to 26.0) and 14.0% (95% CI 7.0 to 22.0) were positive for Cryptosporidium and microsporidia, respectively, by the molecular method. The predominant species of microsporidia in patients was Enterocytozoon bieneusi (85.7% [95% CI 57.0 to 98.0]) and Encephalitozoon cuniculi (14.3% [95% CI 1.7 to 42.0]), which were found by quantitative real-time PCR and its high-resolution melting tool.

Conclusions: As far as we know, this study is the first to estimate the prevalence of infection with Cryptosporidium and microsporidia among HIV-infected persons in northwest of Iran. The prevalence of intestinal microsporidiosis and cryptosporidiosis in this area in HIV-infected people was higher than the global prevalence of infection among immunocompromised patients. In addition to the need for further studies to prove protozoan pathogenicity in the aforementioned group, preventive measures should be considered.

Background: The therapeutic strategy for mycetoma relies heavily on the identification of the causative agents, which are either fungal or bacterial. While histopathological examination of surgical biopsies is currently the most used diagnostic tool, it requires well-trained pathologists, who are lacking in most rural areas where mycetoma is endemic. In this work we propose and evaluate a machine learning approach that semi-automatically analyses histopathological microscopic images of grains and provides a classification of the disease as eumycetoma or actinomycetoma.

Methods: The computational model is based on radiomics and partial least squares. It is assessed on a dataset that includes 890 individual grains collected from 168 patients originating from the Mycetoma Research Centre in Sudan. The dataset contained 94 eumycetoma cases and 74 actinomycetoma cases, with a distribution of the species among the two causative agents that is representative of the Sudanese distribution.

Results: The proposed model achieved identification of causative agents with an accuracy of 91.89%, which is comparable to the accuracy of experts from the domain. The method was found to be robust to a small error in the segmentation of the grain and to changes in the acquisition protocol. Among the radiomics features, the homogeneity of mycetoma grain textures was found to be the most discriminative feature for causative agent identification.

Conclusion: The results presented in this study support that this computational approach could greatly benefit rural areas with limited access to specialized clinical centres and also provide a second opinion for expert pathologists to implement the appropriate therapeutic strategy.

The current study aimed to determine the prevalence of Toxoplasma gondii in ABO blood groups and assess the relationship between the prevalence of T. gondii and blood groups. A literature search was carried out for epidemiological studies that were published through December 2022. A random effects model was used to determine the OR and the pooled prevalence with a 95% CI. The estimated pooled prevalences of T. gondii infection in the A, B, AB and O blood groups were 38% (95% CI 27 to 48%), 38% (95% CI 29 to 47%), 36% (95% CI 26 to 45%) and 36% (95% CI 27 to 45%), respectively. Also, the pooled ORs of the relationship between the prevalence of T. gondii infection and the A, B, AB and O blood groups were 1.08 (95% CI 0.97 to 1.19), 1.10 (95% CI 0.95 to 1.28), 1.08 (95% CI 0.92 to 1.27) and 0.89 (95% CI 0.80 to 1.00), respectively. This meta-analysis did not show any relationship between the prevalence of T. gondii infection and ABO blood groups.

Background: Chronic hepatitis B (HB) remains a significant global health concern, despite the widespread availability of the HB vaccine. While the standard vaccine demonstrates an impressive serological response rate exceeding 90%, a subset of individuals exhibit suboptimal immunity. This study aims to elucidate the efficacy of the AS04C-adjuvanted HB vaccine in addressing non-responsiveness.

Methods: Conducted at the Preventive Medicine Service of the University Albacete Hospital in Spain from 2017 to 2021, this single-center observational study enrolled 195 patients. Among them, 126 (65%) were classified as non-responders following one or two complete standard vaccination courses.

Results: After the administration of a complete four-dose regimen of the AS04C-adjuvanted vaccine, 73.81% of non-responder patients exhibited antibody titers indicative of robust immunity (anti-HBs >10).

Conclusions: These findings underscore the pivotal role of the AS04C-adjuvanted HB vaccine in addressing non-responsiveness, emphasizing its potential as a crucial tool in augmenting immunization strategies for various populations. This includes non-responders to standard vaccination, individuals with chronic kidney disease, those requiring seroprotection due to factors like immunosuppression or occupational hazards, as well as patients for whom conventional revaccination strategies have proven futile. Additional research is needed to expand on the promising results obtained through our protocol.

Scrub typhus is one of the most neglected tropical diseases, a leading cause of acute undifferentiated febrile illness in areas of the 'tsutsugamushi triangle', diagnosed frequently in South Asian countries. The bacteria Orientia tsutsugamushi is the causative agent of the disease, which enters the human body through the bite of trombiculid mites (also known as chiggers) of the genus Leptotrombidium deliense. Diagnosis of the disease is challenging, as its early symptoms mimic other febrile illnesses like dengue, influenza and corona viruses. Lack of rapid, reliable and cost-effective diagnostic methods further complicates the identification process. Northeast India, a mountainous region with a predominantly rural tribal population, has witnessed a resurgence of scrub typhus cases in recent years. Various ecological factors, including rodent populations, habitat characteristics and climatic conditions, influence its prevalence. Entomological investigations have confirmed the abundance of vector mites, highlighting the importance of understanding their distribution and the probability of transmission of scrub typhus in the region. Proper diagnosis, awareness campaigns and behavioural interventions are essential for controlling scrub typhus outbreaks and reducing its impact on public health in Northeast India. Further research and community-based studies are necessary to accurately assess the disease burden and implement effective prevention strategies.

Ensuring primary healthcare (PHC) accessibility to older people with multimorbidity is vital in preventing unnecessary health deterioration. However, older people ≥50 y of age in low- and middle-income countries (LMICs) face challenges in effectively accessing and utilizing PHC. A systematic review was conducted adopting the Andersen-Newman theoretical framework for health services utilization to assess evidence on factors that affect access to PHC by older people. This framework predicts that a series of factors (predisposing, enabling and need factors) influence the utilization of health services by people in general. Seven publications were identified and a narrative analytical method revealed limited research in this area. Facilitating factors included family support, closeness to the PHC facility, friendly service providers and improved functional status of the older people. Barriers included long distance and disjointed PHC services, fewer health professionals and a lack of person-centred care. The following needs were identified: increasing the number of health professionals, provision of PHC services under one roof and regular screening services. There is a need for more investment in infrastructure development, coordination of service delivery and capacity building of service providers in LMICs to improve access and utilization of PHC services for older people.