Volume 14 · Issue 02 · 2025

Leptospirosis, a zoonotic disease caused by pathogenic species of the genus Leptospira, is an important public health concern globally. Leptospirosis has been notifiable under statute in China since 1955, and its epidemiological characteristics have evolved during near 70 years. This study aimed to describe the spatial and temporal patterns and demographic characteristics of leptospirosis from 1955 to 2022 in China, and explore the possible factors that influence leptospirosis transmission risk.

Wavelet time series analysis, global Moran’s I coefficients, space-time scanning statistics, and so on were used to analyze temporal, seasonal, geographic, and demographic trends in leptospirosis using reported national surveillance data from Chinese mainland from 1955 to 2022. Additionally, a Bayesian spatiotemporal model was used in a preliminary analysis to explore potential factors associated with leptospirosis occurrence.

Between 1955 and 2022, China reported 25,236,601 leptospirosis cases, with 91% occurring from July to October. The annual incidence rate peaked at 38.28/100,000 during outbreaks in the 1960s-1980s but stabilized at a low level (0.07/100,000) between 2005 and 2022, with over 99% of cases in southern China. Clustering increased over time, being greatest during the period 2015-2022 (Moran’s I = 0.41, P< 0.01). Space-time cluster analysis indicated that the most likely clusters were in northern provincial-level administrative divisions (PLADs) from 1955 to 1984, in southern PLADs from 1985 to 2022. The main identified risk factors of leptospirosis occurrence were annual average precipitation (3.68, 95% CI: 2.50 to 5.12), GDP per capita (-3.70, 95% CI: -5.97 to -1.41), and the total power of agricultural machinery (-2.51, 95% CI: -3.85 to -1.17).

Over past 70 years, leptospirosis in China has occurred as significant outbreaks but has ultimately declined to stable, low levels of occurrence. However, a clear north-south disparity persists, with tropical and subtropical regions in southern China remaining high-risk areas. The nearly 70-year dataset underscores the complex interplay of climate and socioeconomic factors influencing the disease’s occurrence. Targeted prevention and control measures are critical to prevent outbreaks, especially in regions prone to extreme climatic events like heavy rainfall and floods, which may signal the resurgence of leptospirosis.

Schistosoma haematobium and S. mansoni are endemic in Madagascar, but reliable diagnostic tools are often lacking, contributing to exacerbate transmission and morbidity. This study evaluated the diagnostic accuracy of three tests for schistosome infection in Malagasy adults from areas of medium to high endemicity.

This cross-sectional study enrolled adults from three primary health care centres in Madagascar. Urine and blood samples were tested for schistosome infection using polymerase chain reaction (PCR), up-converting reporter particle lateral flow for the circulating anodic antigen (UCP-LF CAA), and point-of-care circulating cathodic antigen (POC-CCA) tests. Bayesian latent class models were used to assess diagnostic accuracies and disease prevalence.

Of 1339 participants, 461 were from S. haematobium and 878 from S. mansoni endemic areas. Test detection rates were 52% (POC-CCA), 60% (UCP-LF CAA), and 66% (PCR) in the S. haematobium area, and 54%, 55%, and 59% respectively in the S. mansoni area. For S. haematobium, PCR and UCP-LF CAA showed high sensitivity (Se, median 95.2% and 87.8%) but moderate specificity (Sp, 60.3% and 66.2%), while POC-CCA performed moderately (Se: 64.5%; Sp: 59.6%). For S. mansoni, PCR and POC-CCA demonstrated high diagnostic accuracy (Se > 90%, Sp > 80%), while UCP-LF CAA showed good sensitivity (79.9%) but moderate specificity (69.7%).

While population-level prevalence estimates were similar across tests, individual-level agreement was only low to moderate. Our findings suggest that optimal diagnostic strategies should be tailored to specific endemic settings, continued development of accurate diagnostics suitable for highly endemic settings remains a priority.

Hookworm disease remains a global health issue. In China, it persists with a 0.67% infection rate and uneven distribution in 2021. Optimized control strategies are needed. This study aims to optimize intervention strategies for hookworm disease in China.

Structural analysis and parameter estimation were conducted using system dynamics theory. Key variables were identified via the Delphi method, leading to the creation of a causal loop diagram (CLD) and stock flow chart (SFC). Based on the SFC, parameter estimation and quantitative relationships were established and the model was validated. A cost-effectiveness model was then integrated into the intervention mechanism model. Various intervention measures were tested in the model to determine their cost-effectiveness ratio (CER) and effectiveness. Generalized linear models were constructed from simulation data, accounting for the impact of survey sites. The results were used to develop an optimized strategy for hookworm disease control.

In comparing drug treatment methods, whole population deworming (WPD) and key population deworming (KPD) showed lower CERs than examination and voluntarily deworming (EVD), saving 384.79–504.64 CNY and 354.35–506.21 CNY per infection reduced, respectively (P < 0.001). For WPD or KPD alone, CER decreased with increased drug coverage. For examination and deworming (ED) and EVD, CER was highest at 30% coverage for a 1-year intervention, but at 90% coverage for 2–5 years (P < 0.05). WPD, ED, and EVD had higher infection reduction rates than KPD, with ratios of 0.14–0.25, 0.10–0.19, and 0.08–0.17, respectively, over 1–5 years (P < 0.001). Continuous health education over 1–5 years showed that increasing coverage from a 10% baseline led to enhancing cost-effectiveness and intervention outcomes.

In high-endemic areas (infection rate ≥ 20%) in China, prioritize WPD for better cost-effectiveness and outcomes. In medium-endemic areas (5% ≤ infection rate < 20%) where WPD isn’t feasible, use ED for cost-effectiveness and KPD for infection reduction, based on local needs. In low-endemic areas (infection rate < 5%), encourage voluntary examination and treatment due to limited cost-effectiveness of mass treatment. Combining drug treatment with extensive health education can enhance long-term control effect. This strategy can guide control efforts for hookworm diseases in China. Clinical trial number: Not applicable.

Headlice are prevalent worldwide, with a higher burden in rural, lower-middle income settings. They can cause intense itchiness, discomfort, and secondary bacterial infections with potentially serious consequences. Ivermectin is efficacious against headlice, and is also being evaluated as a malaria vector control tool. In this study, we explored risk factors for headlice, and assessed the efficacy of ivermectin mass drug administration (MDA) designed for malaria against headlice.

We conducted an open-label, assessor-blind, cluster-randomized controlled trial in Mopeia, Mozambique. A single dose of ivermectin was given monthly to eligible humans or humans and livestock (humans: 400 μg/kg, livestock: 1% injectable 200 μg/kg) in 3 consecutive months during the rainy season. The control group received albendazole (humans only). Thirty-nine clusters (13 per arm) were randomly selected for the nested assessment of headlice prevalence. 1341 treated participants were followed up at least once, 1, 2 and 3 months and 382 untreated (ineligible) participants at 3 and 6 months after the first MDA round. Headlice diagnosis was determined by scalp examination. Logistic regression was used to identify risk factors for headlice at baseline, and to estimate the treatment effect at each time point.

A total of 1309 participants were included in the main analysis assessing ivermectin MDA efficacy, and 1332 in the risk factor analysis. The baseline headlice prevalence was 11%. Risk factors included living with a household member with head itch [adjusted odds ratio (aOR)= 48.63, 95% confidence interval (CI): 28.7–82.3, P-value < 0.0001], being female (aOR= 2.25, 95% CI: 1.33–3.80, P-value < 0.01), and using surface water as the main water (aOR= 2.37, 95% CI: 1.12–5.33, P-value= 0.04). The treated population receiving ivermectin had significantly lower odds of having headlice at 3 months compared to those receiving albendazole (aOR= 0.19, 95% CI: 0.04–0.91, P-value = 0.04). There was no indirect effect on headlice among children ineligible for treatment.

In a highly endemic setting, mass drug administration with ivermectin significantly reduces headlice infestation prevalence among those who receive the drug for three sequential months. The lack of effect among untreated, ineligible children implies that additional interventions would be needed to interrupt local transmission.

Antimicrobial resistance (AMR) represents a critical global health threat, necessitating the identification of factors that contribute to its emergence and proliferation. We used a "One Health" perspective to evaluate the association of human and veterinary antibiotic usage, environmental factors, socio-economic factors, and health care factors with clinical AMR in China.

We analyzed data from 31 provincial-level administrative divisions in China, encompassing 20,762,383 bacterial isolates sourced from the China Antimicrobial Resistance Surveillance System dataset between 2014 and 2022. A β regression model was used to explore the relationship of AMR with multiple variables. We also estimated the contribution of factors associated with AMR, and evaluated the avoidable risk of AMR under six different measures during 2019 according to available guidelines.

AMR had positive associations with human antibiotic usage, veterinary antibiotic usage, particulate matter smaller than 2.5 µm (PM_2.5) level, population density, gross domestic product per capita, and length of hospital stay, and a 1 unit increase in the level of above independent variables were associated with a percentage change in the aggregate AMR of 1.8% (95% CI: 1.1, 2.5), 2.0% (95% CI: 0.6, 3.4), 0.9% (95% CI: 0.4, 1.4), 0.02% (95% CI: 0.01, 0.03), 0.5% (95% CI: 0.1, 0.8), and 8.0% (95% CI: 1.2, 15.3), respectively. AMR had negative associations with city water popularity, city greenery area per capita, and health expenditure per capita, and a 1 unit increase in the level of above independent variables were associated with a percentage change in the aggregate AMR of -4.2% (95% CI: -6.4, -1.9), -0.4% (95% CI: -0.8, -0.07), and -0.02% (95% CI: -0.04, -0.01), respectively. PM_2.5 might be a major influencing factor of AMR, accounting for 13.7% of variation in aggregate AMR. During 2019, there was estimated 5.1% aggregate AMR could be attributed to PM_2.5, corresponding to 25.7 thousand premature deaths, 691.8 thousand years of life lost, and 63.9 billion Chinese yuan in the whole country. Human antibiotic usage halved, veterinary antibiotic usage halved, city water popularity improved, city greenery area improved, and comprehensive measures could decrease nationwide aggregate AMR by 8.5, 0.5, 1.3, 4.4, and 17.2%, respectively.

The study highlights the complex and multi-dimensional nature of AMR in China and finds PM_2.5 as a possible major influencing factor. Despite improvements in decreasing AMR, future initiatives should consider integrated strategies to control PM_2.5 and other factors simultaneously to decrease AMR.

Oral emtricitabine-tenofovir disoproxil fumarate (F/TDF) for HIV pre-exposure prophylaxis (PrEP) demonstrates dual potential through antiviral activity against hepatitis B virus (HBV). While F/TDF lacks activity against hepatitis C virus (HCV), the use of F/TDF for HIV PrEP may elevate HCV risk through risk compensation. This study aims to investigate HBV/HCV incidence among men who have sex with men (MSM) using F/TDF-based HIV PrEP, addressing evidence gaps in low- and middle-income countries.

We conducted a secondary analysis of the China Real-World Oral Intake of PrEP (CROPrEP) study, a multicenter prospective cohort of MSM (F/TDF users/non-users) from Beijing, Shenyang, Shenzhen, and Chongqing. Participants underwent HBV/HCV testing at baseline and at the 12-month follow-up. Only HBV-susceptible (hepatitis B surface antigen-negative, hepatitis B surface and core antibody-negative) MSM were included in the secondary analysis, to calculate HBV incidence. The primary outcomes were HBV/HCV incidence rates at the 12-month follow-up. Bayesian Poisson regression identified HBV/HCV infection risk factors.

The CROPrEP cohort prospectively recruited 1023 F/TDF users and 507 F/TDF non-users at baseline. This secondary analysis included 259 F/TDF users and 120 non-users identified as HBV-susceptible at baseline. At the 12-month of follow-up, no incident HBV infections occurred in the F/TDF users group, and only one incident HBV infection occurred in the F/TDF non-users group. The incidence of new HBV infections was 0.00/100 person-years (PY) [95% confidence interval (CI): 0.00-1.32] among HBV-susceptible F/TDF users and 0.77/100 PY (95% CI: 0.02–4.20) among HBV-susceptible F/TDF non-users. HBV incidence was reduced with F/TDF compared with no F/TDF [adjusted incidence rate ratio (aIRR): 0.00; 95% CI: 0.00–0.00]. HCV incidence among F/TDF users and non-users was 0.31/100 PY (95% CI: 0.06–0.90) and 0.00/100 PY (95% CI: 0.00–0.74) after 12 months, respectively. HCV incidence was lower in F/TDF non-users than in F/TDF users (aIRR: 0.00; 95% CI: 0.00–0.25).

This study suggests a potential benefit in reducing HBV incidence among MSM using F/TDF as HIV PrEP, highlighting the potential for integrated prevention strategies addressing both HIV and HBV risks in PrEP programmes.

Maternal influenza vaccine hesitancy plays a vital role in the low rates of vaccination. However, instruments to appropriately assess perinatal influenza vaccine hesitancy are unavailable. This study aimed to develop the Maternal Influenza Vaccine Hesitancy Scale based on the 5C vaccination hesitancy scale, containing the subscales of confidence, complacency, constraints, calculative, and collective responsibility, and to provide a preliminary overview of the current hesitancy on maternal influenza vaccination in China.

A cross-sectional survey, from January to March 2024, was carried out among 2035 pregnant and postpartum women from nine provincial-level administrative divisions representing eastern, central, western, and northeastern areas of China. Reliability was evaluated by internal consistency reliability and split-half reliability, and a Cronbach’s alpha coefficient > 0.7 was considered acceptable. Construct validity was assessed using confirmatory factor analysis (CFA), with good model fit defined as root mean square error of approximation (RMSEA) < 0.100, normed fit index (NFI) > 0.9, comparative fit index (CFI) > 0.9, and Tucker-Lewis index (TLI) > 0.9.

Confirmatory factor analysis results supported the five-factor structure of the scale (RMESA= 0.098, CFI = 0.921, TLI = 0.903, NFI = 0.918). The Cronbach’s alpha coefficients for the scale as well as the subscales ranged from 0.802 to 0.958. Among five subscales, collective responsibility (2.73 ± 0.63) scored highest, while complacency (2.16 ± 0.69) and constraints (2.17 ± 0.69) were the lowest.

The Maternal Influenza Vaccine Hesitancy Scale developed in this study is a reliable and valid instrument to measure the influenza vaccine hesitancy of pregnant and postpartum women. It is recommended that interventions including health education and improving the access to the vaccination service be carried out to reduce the maternal influenza vaccination hesitancy.

Historically, onchocerciasis has been recognised for its dermatological and ophthalmological manifestations, such as blindness. However, growing epidemiological evidence indicates that onchocerciasis is also associated with neurological complications, particularly onchocerciasis-associated epilepsy (OAE). These complications are not currently reflected in disease burden estimates and associated disability-adjusted life years (DALYs) for onchocerciasis.

The most recent global burden of disease estimates for onchocerciasis in 2019 reported 1.23 million DALYs without accounting for OAE. Yet, a preliminary study suggested that 128,000 years of life lost to disability (YLD, a key component of DALYs) may be attributable to epilepsy in onchocerciasis-endemic areas of East and Central Africa. This figure, which would represent over 13% of the total onchocerciasis morbidity burden and 10% of the global epilepsy morbidity burden, is likely still an underestimation. Current disability weights for epilepsy YLD estimation may not fully capture the spectrum of OAE, which often involves nodding syndrome, developmental delays, motor disabilities, cognitive impairments and stigma. In regions where access to antiseizure medication treatment is sparse, poorly controlled seizures can exacerbate disability and lead to premature mortality. Targeted integrated strategies—combining onchocerciasis control measures with improved epilepsy care—could help address these critical gaps.

Recognising OAE as part of the disease burden associated with onchocerciasis may encourage global health stakeholders to allocate resources for targeted interventions, thereby refining disease burden estimates, reducing disability, averting premature deaths and improving overall health outcomes.

While mRNA vaccines represent a transformative platform for infectious disease control, their efficacy in antigen-presenting cells (APCs) remains vulnerable to endogenous regulatory networks, particularly microRNA (miR)-mediated translational suppression. This study addresses a critical gap in current vaccine design paradigms by systematically investigating host miR interference – an understudied barrier to robust antigen production.

APCs express cell-type-specific miR repertoires capable of binding vaccine mRNAs through conserved seed sequences, as evidenced by synthesis of experimental data from 67 studies demonstrating miR-mediated repression of exogenous transcripts. To decode these inhibitory interactions, the commentary proposes an integrated multi-omics framework combining Argonaute immunoprecipitation with crosslinking-based miR-mRNA interactome sequencing, enabling precise mapping of miR-vaccine mRNA binding events in vaccine-transfected APCs. Furthermore, the commentary suggests two actionable strategies for evading miR interference: (1) Synonymous codon optimization at seed-match regions, achieving binding energy reduction while preserving antigenicity through degeneracy of genetic coding; (2) Targeted co-delivery of miR inhibitors. By bridging host RNA biology and vaccine engineering, this work provides a blueprint for developing miR-resistant mRNA vaccines for public health interventions.

miRs may inhibit mRNA vaccine translation in APCs, potentially reducing antigen production and weakening the resulting immune response. To address this, next-generation mRNA vaccines should incorporate "miR-proofing" strategies during design to avoid miR interference.