Infectious Diseases of Poverty最新文献

Background: Loiasis affects millions in Central Africa and, though historically considered benign, emerging data suggest possible renal involvement. This study investigated the association between Loa microfilaremia and renal function.

Methods: We conducted a cross-sectional study in the Republic of Congo in May-June 2022. Renal function was assessed via estimated glomerular filtration rate (eGFR) using Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) and European Kidney Function Consortium (EKFC) equations, and proteinuria and/or haematuria (renal abnormalities, RAb). Multinomial logistic regression assessed associations between microfilarial density (MFD) and chronic kidney disease (CKD), using EKFC with Dubois correction. Population attributable fractions were estimated from a logistic model including Loa microfilaremia as a binary variable (present versus absent).

Results: Among 986 participants, CKD prevalence ranged from 13.4% [95% confidence interval (CI) 11.4-15.7%, CKD-EPI] to 17.6% (95% CI 15.3-20.1%, EKFC) for KDIGO stages 1-5, and from 3.0% (95% CI 2.1-4.3%, CKD-EPI) to 7.6% (95% CI 6.1-9.4%, EKFC) for stages 3-5. Loa MFD was associated with higher odds of CKD, particularly in individuals with RAb. Compared to amicrofilaremic participants, those with Loa MFD ≥ 20 000 mf/ml had significantly increased risk: adjusted relative risk ratio (aRRR) for CKD severity categories (≤ 2nd, 2nd-10th, 10th-50th, > 50th eGFR percentile) with RAb were 8.67 (95% CI 2.62-28.64, P = 0.021), 14.26 (95% CI 3.41-59.68, P < 0.001), 5.50 (95% CI 0.55-61.78, P = 0.145), and 26.21 (95% CI 1.64-417.84, P = 0.021). Population attributable fractions of CKD stages 1-5 to Loa microfilaremia was 14.7% (95% CI 4.3-24.0) and 30.1% (95% CI 16.2-42.8) for CKD stages 1-5 with RAb.

Conclusions: This study provides the first epidemiological evidence linking loiasis to renal impairment, likely via glomerular damage. Given loiasis high endemicity in Central Africa, it may contribute to the burden of unexplained nephropathies. Longitudinal studies and renal biopsies are warranted to clarify underlying mechanisms.

Background: Toxoplasma gondii is a globally widespread zoonotic parasite, infecting nearly one-third of the human population, often leading to chronic, latent infections. Among the emerging layers of gene regulation, 5-methylcytosine (m⁵C) has emerged as a pivotal post-transcriptional modification in eukaryotes. Despite its growing recognition in various species, the epitranscriptomic landscape of m⁵C in the tachyzoite stage of T. gondii remains largely unexplored. To address this gap, we performed the first comprehensive m⁵C methylation profiling across three major T. gondii genotypes-RH (type I), ME49 (type II), and VEG (type III).

Methods: The comparative m⁵C methylation analysis was carried out using methylated RNA immunoprecipitation sequencing (MeRIP-Seq) combined with RNA sequencing (RNA-Seq). Differentially m⁵C-methylated genes (DMMGs) were functionally annotated via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. By combining methylation and transcriptomic data, we uncovered strain-specific correlations between m⁵C modifications and gene expression. Additionally, expression and methylation patterns of potential regulators identified via BLASTP searches were examined. Statistical analyses were determined by one-way ANOVA.

Results: Our analysis revealed a total of 5129, 4968, and 4577 m⁵C-methylated genes in RH, ME49, and VEG tachyzoites, respectively, with methylation predominantly enriched in the coding sequences. Comparative analysis across different strains uncovered 1710, 1131, and 784 DMMGs in RH versus ME49, RH versus VEG, and ME49 versus VEG, respectively. Functional enrichment analysis highlighted key biological processes, including catalytic activity, transport, phospholipid metabolism and transcription regulation. Furthermore, KEGG pathway analysis identified critical m⁵C-regulated processes such as nucleocytoplasmic transport, DNA replication, and ATP-dependent chromatin remodeling. Virulence-associated secretory effectors exhibited hypermethylation in more virulent strains, such as GRA39 and ROP35. Additionally, several putative m⁵C regulators displayed genotype-specific or conserved expression and methylation patterns.

Conclusions: This study presents the first m⁵C epitranscriptomic atlas of T. gondii tachyzoites, revealing both conserved and genotype-specific mRNA modification networks. These insights significantly increased the understanding of the regulatory role of m⁵C in T. gondii pathogenesis and open promising avenues for the development of vaccines and therapeutics aimed at combating zoonotic toxoplasmosis.

Background: Malaria and anemia remain a major public health problem in Sub-Saharan Africa, with pregnant women being particularly vulnerable to its adverse effects. Despite significant efforts to control malaria and anemia, the burden and adverse effects persist, especially in developing countries among pregnant women. Existing studies investigated malaria and anemia separately and identified individual-level factors as contributors to malaria or anemia, yet the influence of community-level factors remains underexplored. This study aimed to assess the malaria-anemia comorbidity and its determinants among pregnant women in high- and moderate-malaria-risk countries in Sub-Saharan Africa.

Methods: Data from the Malaria Indicator Surveys (MIS) conducted between 2016 and 2022 across 17 Sub-Saharan African countries were used for analysis. The study included a total of 50,545 weighted samples. Multilevel logistic regression was used to assess individual and community-level factors associated with malaria-anemia comorbidity. Factors associated with malaria-anemia comorbidity were considered significant at P-values < 0.05. A model with the lowest deviance and highest log-likelihood ratio was selected as the best-fit model.

Results: The pooled prevalence of malaria-anemia comorbidity among pregnant women was 39.00% (95% CI 29.00-49.00). No formal education (OR = 1.43, 95% CI 1.34-1.54), using untreated bed nets (OR = 1.23, 95% CI 1.16-1.30), poor wealth index (OR = 2.37, 95% CI 2.18-2.57), not using indoor residual spraying (OR = 2.15, 95% CI 1.87-2.48), households without a television (OR = 1.33, 95% CI 1.23-1.44), rural residence (OR = 2.73, 95% CI 2.54-2.93), and residing in West Sub-Saharan Africa (OR = 8.00, 95% CI 7.47-8.57), Central Sub-Saharan Africa (OR = 6.76, 95% CI 76.03-7.57), and South Sub-Saharan Africa (OR = 18.76, 95% CI 17.3-20.4) were determinants of malaria-anemia comorbidity.

Conclusions: This study revealed high malaria-anemia comorbidity among pregnant women in high- and moderate-malaria-risk countries in sub-Saharan Africa, with both individual- and community-level factors as significant determinants. Health policies should prioritize targeted interventions for pregnant women, especially in rural areas, with an emphasis on increasing untreated bed net use, and region-specific strategies, particularly in West, Central, and South Sub-Saharan Africa, where malaria-anemia comorbidity burden is notably high.

Background: Despite the high coverage of childhood vaccination, pertussis remains a significant global health challenge, with increasing adult cases attributed to waning immunity and enhanced diagnostic capability. This study quantified the global burden of pertussis in adults from 1990 to 2021 and evaluated the impact of the COVID-19 pandemic on disease trends.

Methods: Using data from the Global Burden of Disease Study 2021, we assessed pertussis incidence and disability-adjusted life years (DALYs) in adults, stratified by age, sex, sociodemographic factors, and geographic regions. Temporal trends were analysed using joinpoint regression to detect significant changes and calculate the average annual percentage change (AAPC). An exponential smoothing state-space model with hierarchical forecast reconciliation was used to estimate the impact of the COVID-19 pandemic on pertussis burden.

Results: Globally, the incidence rate of adult pertussis declined from 17.44 per 100,000 population in 1990 to 9.00 per 100,000 in 2019, and fell sharply to 2.70 per 100,000 by 2021. DALYs rates followed a similar trend. The burden was consistently highest in low Socio-demographic Index (SDI) countries, where the 2019 incidence rate was over four times that of high SDI countries (18.59 vs. 3.96 per 100,000). Between 1990 and 2019, incidence numbers increased in low SDI countries [AAPC: 0.63%; 95% confidence interval: 0.36%, 0.91%] and in older adults (AAPC > 0), despite falling incidence rates. From 2009 to 2019, incidence rates increased in 84 countries. During the COVID-19 pandemic, estimates based on the model indicated a 58.41% reduction in incidence and a 50.34% decrease in DALYs.

Conclusions: Although the global incidence of adult pertussis has declined over the past three decades, a resurgence from 2009 to 2019, particularly in low-income regions and specific age groups, underscores the persistent challenges. The sharp decline during the COVID-19 pandemic highlights the importance of public health and social measures. These findings emphasise the need for targeted vaccination strategies and sustained surveillance to address regional disparities and prevent the resurgence of the disease.

Background: Mosquitoes with aggressive biting behavior are important disease vectors threatening public health. Armigeres subalbatus, as an emerging arbovirus and filarial disease vector, exhibits aggressive host-seeking behavior and unique breeding preference for contaminated water. However, the molecular mechanisms underlying these biological characteristics remain poorly understood. This study aimed to generate a high-quality genome assembly and characterize the genetic basis of vector competence and environmental adaptation in Ar. subalbatus.

Methods: We sequenced and assembled the Ar. subalbatus genome using Oxford Nanopore long-read sequencing, Illumina short-read sequencing, and Hi-C technology. Comparative genomic analysis was performed to identify gene families related to detoxification, diapause, innate immunity, and sex determination. Gene structure analysis focused on the male-determining factor and its evolutionary relationships with other mosquito vectors.

Results: The genome assembly consists of three chromosomes, with a total size of 1.33 Gbp and an N50 of 430.15 Mbp (GenBank assembly: GCA_024139115.2), displaying 99.4% Benchmarking Universal Single-Copy Orthologs (BUSCO) completeness. We identified the gene structure of the male-determining factor (AsuMf) and characterized its evolutionary relationship with other mosquito vectors. The analysis revealed expanded detoxification-related gene families including cytochrome P450s, which may facilitate adaptation to contaminated breeding sites. We characterized 566 putative diapause-related genes that could potentially contribute to geographical expansion, 334 innate immune genes, and 1673 endogenous viral elements, indicating complex virus-host interactions throughout evolution.

Conclusions: Our study provides insights into the molecular basis of vector competence and adaptation in Ar. subalbatus. The expanded detoxification gene families may enable the species to survive in polluted environments, while the identified diapause-related genes could explain its geographical expansion capabilities. These findings establish a foundation for developing novel vector control strategies targeting this emerging disease vector.

Asian hepatointestinal schistosomiasis due to Schistosoma japonicum is prevalent in the Philippines and in Indonesia, while it is close to elimination in China. The second Asian schistosome, S. mekongi, is found in Cambodia and Laos. The main pathology caused by both species is liver fibrosis, which can cause significant morbidity and mortality, mainly due to portal hypertension leading to bleeding from esophageal varices. Ultrasonography was introduced several decades ago as a safe, fast, non-invasive, and relatively inexpensive technique for assessing chronic schistosomiasis-related hepatic pathology in the clinical and field settings. A standardized ultrasound protocol had been established by experts at a WHO-chaired meeting in Cairo, Egypt, in 1990. The peculiarities of sonomorphologic abnormalities caused by S. japonicum and S. mekongi were not sufficiently covered in the Cairo protocol and not addressed at all in the subsequent WHO chaired meeting in Niamey 1996. At a follow-up WHO-chaired meeting in Phnom Pehnh, Cambodia, in 2002, an attempt was made to develop a protocol for Asian schistosomiasis, but a protocol resulting from this meeting has never been published. Although several studies investigated the use of ultrasonography to assess S. japonicum- and S. mekongi-related sonomorphological morbidity across endemic areas the lack of a standardized protocol hampered the characterization of sonomorphologic abnormalities with regard to progression, reversibility, prognosis, and correlation to morbidity. In addition, the comparison of data from different endemic areas and populations remained difficult. Therefore, a WHO-chiared expert meeting took place in Basel, Switzerland in September 2024 with the aim to establish a standardized ultrasound protocol for reporting the pathology caused by S. japonicum and S. mekongi. The proposed protocol is described in this article.

Background: Plasmodium vivax is the predominant malaria species in many Southeast Asian countries. Eliminating all human malaria species by 2030 requires greater focus on P. vivax, with targeted measures to address its unique challenges. This study evaluated slide positivity rates, temporal trends, and risk factors associated with febrile P. vivax infections in a malaria-endemic district along the Thailand-Myanmar border.

Methods: This study employed a community-based longitudinal surveillance design over six years (January 2018-December 2023). Data were collected through routine passive case detection at field malaria clinics using extended, standardized case record forms. Malaria diagnosis was conducted via microscopy examination. Descriptive statistics and logistic regression models were used for data analysis.

Results: Among 13,347 febrile malaria-suspected patients, the cumulative slide positivity rate for P. vivax was 11.0%. Although no distinct seasonal peaks were observed, P. vivax cases generally increased in April and again in November and December. Multivariable logistic regression analysis identified several significant risk factors for febrile P. vivax infection, including school-aged children (5-14 years) (aOR: 1.56, 95% CI: 1.24-1.97), working-age adults (15-34 years) (aOR: 1.43, 95% CI: 1.02-2.00), males (aOR: 1.19, 95% CI: 1.06-1.35), Myanmar nationals (aOR: 2.37, 95% CI: 2.01-2.80), and other non-Thai nationals, such as individuals from Laos and Cambodia (aOR: 5.50, 95% CI: 3.36-8.90). A history of malaria (aOR: 1.59, 95% CI: 1.38-1.83), recent travel within two weeks (aOR: 2.38, 95% CI: 1.94-2.92), and engagement in livestock-related occupations (aOR: 2.49, 95% CI: 1.14-5.35) were also associated with higher odds of infection. In contrast, being unemployed (aOR: 0.55, 95% CI: 0.36-0.81), working in occupations such as maid, driver, or teacher (aOR: 0.78, 95% CI: 0.66-0.93), and consistent use of bed nets (aOR: 0.39, 95% CI: 0.30-0.51) significantly reduced infection risk.

Conclusions: This study identified a relatively high slide positivity rate of febrile P. vivax infection in a malaria-endemic district in western Thailand along the Myanmar border. Strengthening malaria surveillance, targeting high-risk populations, ensuring treatment adherence, and promoting early care-seeking behavior are crucial for reducing P. vivax transmission and advancing malaria elimination efforts.

Background: The Global Burden of Disease (GBD) study offers influential Disability-Adjusted Life Years (DALYs) estimates for various diseases. However, discrepancies with national surveillance data raise concerns about accuracy. This study aims to promote the deep integration of the GBD model with localized data and facilitate the development of region-specific models.

Methods: Data for 14 notifiable infectious diseases (NIDs), grouped into intestinal infectious diseases, respiratory infectious diseases, and sexually transmitted and blood-borne infections, were obtained from the Data-center of China Public Health Science. DALYs based on national surveillance data (2010-2020) were calculated using DALY formulas, and discrepancies with GBD estimates were quantified through ratio comparisons. A historical timeline map highlighted key infectious disease control policies and certified disease elimination events in China.

Results: National surveillance data show a decrease in DALYs for 14 NIDs in China, from 6,529,124.62 person-years in 2010 to 6,326,497.18 person-years in 2020. Among them, sexually transmitted and blood-borne infections have the highest burden, with 78% of DALYs attributed to hepatitis B (4,864,028.29 person-years). Respiratory infectious diseases follow, with 99% of DALYs from TB (394,927.70 person-years). Intestinal infectious diseases have the relative lightest burden, with 45% of DALYs from hepatitis E (496.49 person-years). Over 11 years, 9 of the 14 NIDs showed a downward trend. Comparisons reveal that DALYs based on national surveillance data are lower than GBD 2021 estimates.

Conclusions: Considerable differences exist between the GBD estimates and national surveillance data regarding the burden of 14 NIDs in China. Therefore, strengthening national reporting systems and integrating localized data with the GBD model is essential for more accurate disease burden assessments and effective response strategies. Despite significant progress in infectious disease control, China still faces substantial challenges in domestic disease elimination.

Background: The importance of patient participation in designing and delivering services for persons affected by neglected tropical diseases (NTDs) has gained increasing recognition. Responding to this, persons affected by NTDs urged NTD-focused non-governmental organisations (NGOs) to take action. These NGOs are pivotal in addressing healthcare disparities and reaching marginalised communities. To address the insufficient progress on participation, a participatory initiative was launched to develop a tool designed to support NGOs in fostering inclusion and ensuring the meaningful engagement of affected persons in their organisational decision-making processes.

Methods: This research used an iterative, mixed-methods approach involving stakeholder input, semi-structured interviews, and surveys across two phases. Phase 1 included exploratory workshops with persons affected by NTDs and NTD NGO employees which led to the development of a first draft of a self-assessment tool. Phase 2 involved piloting the tool in NTD NGOs. Data were gathered via pre- and post-pilot interviews and surveys. Thematic analysis was used for the qualitative data and descriptive analysis for the quantitative data.

Results: In phase 1, exploratory workshops revealed that meaningful participation involves creating environments where affected persons can openly share priorities and build their capacity. Workshop participants emphasised the need of inclusion at all stages of NGO activities. These insights informed the draft NTD Inclusion Scorecard (NISC), covering six domains. In phase 2, ten pilot sessions were conducted, feedback was gathered from 22 interviewees and 43 survey participants, focusing on the NISC's usability and relevance. While feedback on the NISC was positive, participants highlighted the need for contextualisation, organisational commitment, and adding a communication domain to the NISC.

Conclusions: The NISC is a self-assessment tool for NTD organisations, designed to enhance internal decision-making by fostering awareness of the importance of including the perspectives of persons affected by NTDs. By using the NISC, NGOs can identify gaps in inclusion and participation, improve their decision-making processes and provide services that are relevant and impactful for persons affected by NTDs. This tool provides insights that can guide NGOs in strengthening their role in promoting inclusion and increasing the effectiveness of their programmes.

Background: Understanding Plasmodium sexual differentiation is crucial for blocking transmission. This study identified risk factors for gametocyte carriage and gametocytemia in P. vivax and P. falciparum to inform malaria elimination strategies at the China-Myanmar border.

Methods: Gametocytes and asexual parasites were microscopically detected on thick smears collected from 2011 to 2020 in Laiza Township, Kachin State, Myanmar. Mono-/polyclonality were detected by genotyping at Pvmsp3α/β for P. vivax, and Pfmsp1/2 for P. falciparum. Kulldorff's retrospective time scan statistics tested for likely clusters of gametocyte-positive cases over time. Chi-square or Fisher's exact tests compared proportions of gametocyte-positive cases in categorical variables. Generalized linear models assessed risk factors (year, season, demographics, clinical/parasitological features) for gametocyte carriage (logistic regression for a binomial outcome) and gametocytemia (Gaussian regression for continuous outcome), respectively.

Results: During 2011-2020, 8240 patients had P. vivax infections, with 7249 testing positive for gametocytes. Among 510 P. falciparum cases, 56 tested positive for gametocytes. A significant cluster of P. vivax gametocyte carriage occurred from May 2015 to August 2017 (P = 0.001). For P. vivax, dry season, previous malaria history, fever, and parasite density were associated with gametocyte carriage. Gametocyte density increased with asexual parasite density (P < 0.001) but was lower during the rainy season and in those with a history of malaria infection (P < 0.001). Over time, gametocytes carriage proportion increased while density decreased (P < 0.001). For P. falciparum, younger age and previous malaria history were associated with gametocyte carriage, and density was higher in the dry season (P = 0.0115). Polyclonal P. vivax infections had higher gametocyte densities than monoclonal infections (P < 0.0001) and P. falciparum gametocyte density tended to increase with multiplicity of infection.

Conclusions: Younger age, prior malaria infection, travel, and polyclonal infections correlate with higher P. vivax gametocyte prevalence. Gametocyte carriage peakes during the dry season, highlighting the need for seasonal strategies to support malaria elimination. These findings enhance understanding of risk factors for the transmissible stage of the two main human Plasmodium species in the Greater Mekong Subregion border areas.