Journal of Epidemiology and Global Health最新文献

Background: Seasonal influenza is a highly contagious acute respiratory infection that imposes a considerable global health burden. Although numerous investigations have examined the short-term effects of ambient temperature or humidity on influenza incidence, relatively few have addressed their combined effects. To bridge this gap, the present study sought to conduct a time-series analysis to examine the combined effects of temperature and relative humidity on influenza incidence in Japan, while accounting for potential confounders.

Methods: Weekly time-series data on influenza incidence and meteorological factors (i.e., mean temperature (°C), relative humidity (%), precipitation (mm), wind speed (m/s) and sunshine duration (hours)) were collected from all 47 prefectures in Japan from 2010 to 2019. A composite exposure metric, humidex, was calculated to capture the combined effects of temperature and relative humidity. We employed an extended two-stage time-series design. In the first stage, a time-stratified case-crossover design was implemented using conditional quasi-Poisson regression integrated with a distributed lag non-linear model to characterize the humidex-influenza associations at the prefectural level. In the second stage, a multivariate meta-analysis was conducted to derive pooled national estimates.

Results: A total of 14,526,346 influenza cases were analyzed. Overall, an inverted J-shaped association between short-term exposure to humidex and influenza incidence was observed. Decreases in humidex were associated with an increased risk of influenza, with the maximum relative risk (RR) reaching 10.75 (95% confidence interval [CI]: 8.35-3.82). The elevated risk corresponding to low humidex (5th percentile) became apparent at week 0, persisted until week 4, and peaked at approximately week 1 (RR = 3.31, 95% CI: 2.89-4.31). Furthermore, significant geographical heterogeneity in influenza incidence was detected across prefectures (Q = 343.4, p-value < 0.001; I² = 46.4%).

Conclusions: Our findings demonstrates that the combined effects of ambient temperature and relative humidity are significantly associated with an elevated risk of influenza in Japan. These findings underscore the urgent need for bespoke public health interventions tailored to mitigate adverse health outcomes in regions characterized by persistently low humidex values.

Background: The number of food delivery workers engaging in online food delivery (OFD) services has soared recently. While they are exposed to air pollutants from traffic exhaust frequently, their exposure to carbon monoxide (CO) is seldom assessed. This study aimed to assess the CO exposure of food delivery workers using exhaled air with consideration of smoking habits.

Methods: We recruited food delivery workers from OFD services and compared their CO concentrations in exhaled air with those of a reference group. In addition, we used a questionnaire to gather data on sociodemographic characteristics, health behaviors, health status, and work-related conditions.

Results: We enrolled 156 food delivery workers and a reference group of 49 members. The results showed that food delivery workers had a higher mean CO concentration in exhaled air (4.79 ppm vs. 1.51 ppm, p < 0.001) as well as a higher proportion of smokers (25.0% vs. 4.1%, p < 0.001). While food delivery workers with smoking habits had a much higher mean CO concentration in exhaled air than those without smoking habits (14.46 ppm vs. 1.57 ppm, p < 0.001), amongst non-smokers, the CO concentration was still higher in food delivery workers than in the reference group (1.57 ppm vs. 1.13 ppm, p = 0.002). Among smokers, smoking might contribute 89% of the CO in exhaled air.

Conclusions: Food delivery workers had higher CO concentrations in exhaled air than the reference group, indicating higher exposure levels. Smoking is an important contributing factor when using exhaled air for CO exposure assessment.

Background: Cambodia is experiencing a demographic shift likely to increase the burden of noncommunicable diseases (NCDs). Identifying patterns of risk factors among adults can contribute to efforts to effectively target and prevent these chronic diseases. This study aims to examine latent classes of population risk based on behavioral and metabolic risk factors for NCDs in Cambodia.

Methods: Data from 5275 respondents aged 18 and older from the 2023 Cambodian World Health Survey Plus were used for analysis. Latent class analysis identified distinct classes of individuals with similar behavioral and metabolic risk factors. Indicator variables included tobacco and alcohol use, fruit and vegetable diet, physical activity, body mass index, blood pressure, blood glucose, and total cholesterol and triglyceride levels. Multinomial logistic regression was employed to predict latent class membership based on sociodemographic characteristics.

Results: Three distinct latent classes were identified: "alcohol users with lower metabolic risk" (37.8%), "substance users with compounding unhealthy behaviors" (15.0%), and "alcohol users with higher metabolic risk" (47.2%). Men, older adults, and individuals with lower education were more likely to be substance users with compounding unhealthy behaviors and alcohol users with higher metabolic risks.

Conclusions: These findings highlight the need for targeted public health strategies to address the combined impact of multiple risk factors, particularly among men, older adults, and individuals with lower education levels.

Background: Effective response during global health emergencies hinges on the quality of guidelines provided by authoritative organisations like the World Health Organisation (WHO). This study assessed the quality of WHO emergency guidelines disseminated through the Disease Outbreak News (DONs) platform between 2023 and 2024 to identify strengths and weaknesses across established quality domains.

Methods: A total of 115 WHO guidelines issued within DONs were analysed using the AGREE II framework, which evaluates six domains: Scope and Purpose; Stakeholder Involvement; Rigour of Development; Clarity of Presentation; Applicability, and Editorial Independence. Descriptive statistics and one-way repeated measures ANOVA were conducted to determine significant differences among domain scores.

Results: The analysis revealed statistically significant differences across domains, F(2.40, 552.34) = 739.09, p < .001, ηp² = 0.866. The highest mean scores were recorded for Scope and Purpose (M = 6.46) and Clarity of Presentation (M = 6.27), indicating strengths in goal articulation and user accessibility. Conversely, Editorial Independence (M = 2.74) and Rigour of Development (M = 3.26) scored the lowest, pointing to persistent gaps in transparency and methodological robustness.

Conclusions: While WHO guidelines during emergencies perform well in clarity and scope, critical weaknesses remain in transparency, stakeholder engagement, and methodological rigour. These findings indicate the need for more balanced and inclusive guideline development processes to enhance trust and utility during public health emergencies.

Background: Stroke is a leading cause of death in the U.S., with mortality trends influenced by hyperlipidemia, a significant risk factor for atherosclerosis and cardiovascular disease that can lead to ischemic stroke. This analysis examines stroke-related mortality in hyperlipidemia among adults aged 25 and older from 1999 to 2023.

Methods: A retrospective analysis of CDC WONDER investigated trends in mortality from Stroke (ICD codes: I60-I69) among Hyperlipidemia patients (ICD codes: E78.0, E78.1, E78.3, E78.4, E78.5) aged 25 and older. Joinpoint regression analysis calculated age-adjusted mortality rates (AAMR) per 100,000 individuals, annual percentage changes (APC), Average Annual Percent Change (AAPC), and 95% confidence intervals.

Results: Between 1999 and 2023, stroke and hyperlipidemia caused 241,308 deaths, with AAMRs of 1.38 in 1999 and 7.46 in 2023, an AAPC of + 7.16 (95% CI: 6.66 to 8.52). Adult men had higher AAMRs than women, with increases for both sexes [AAPC: + 7.20 vs. + 7.10; p < 0.001]. Black individuals had the highest AAMRs, followed by Hispanics. AAMR rose for all races, notably for Blacks/African Americans (AAPC: + 8.63%) and adults aged 65 and above (AAPC: + 7.35%). Northeast regions have the highest AAMRs, with the Midwest showing the most significant rise (AAPC: + 7.86%). AAMRs varied by state, from 2.0 in Georgia to 9.43 in Vermont in 2023. Non-metropolitan areas had higher AAMRs (4.31) than metropolitan areas (3.54).

Conclusion: This analysis reveals significant demographic and racial disparities in Stroke mortality among U.S. adults with Hyperlipidemia, which highlights the urgent need for targeted, equity-focused interventions to address these disparities.

Respiratory Syncytial Virus (RSV) represents a predominant etiological agent of severe acute lower respiratory tract infections (ALRTIs) among infants and young children in The Gambia, contributing substantially to seasonal peaks in paediatric hospitalizations and mortality during the annual rainy season [1-3]. Despite recent global approvals of maternal RSV vaccines, their operational feasibility and sociocultural acceptability in resource-constrained settings remain inadequately characterized. This cross-sectional, mixed-methods study evaluated these parameters among 179 antenatal and lactating mothers attending Edward Francis Small Teaching Hospital (EFSTH) between June and August 2025, utilizing structured questionnaires complemented by qualitative insights from healthcare providers. Findings revealed critically deficient maternal awareness of RSV: merely 12.8% of participants acknowledged familiarity with the virus, and only 10.6% recognized its potential for life-threatening infant respiratory disease. Healthcare workers constituted the primary information source (82.6%). Paradoxically, willingness to accept maternal RSV vaccination was elevated (81.6% during pregnancy; 74.9% during lactation), predominantly motivated by trust in clinical recommendations. Primary barriers included safety apprehensions (88.8%), vaccine unavailability (41.9%), and limited awareness (79.3%). Multiparity significantly correlated with gestational vaccine acceptance (p = 0.004), while tertiary education predicted RSV awareness (p = 0.022). Hospital-based administration was preferred (88.3%). This study concludes that while maternal RSV vaccination is broadly acceptable in The Gambia, profound knowledge deficits and systemic impediments especially safety concerns and supply chain limitations compromise feasibility. Programmatic success necessitates integration into antenatal care (ANC) frameworks, provider-driven education initiatives, and fortified cold chain logistics. These evidence-based insights offer actionable guidance for policymakers developing context-specific maternal immunization strategies to mitigate infant RSV burden in analogous low-resource settings.

Background: Healthcare-associated infections (HCAIs) pose a serious threat to healthcare systems. Accurately determining the incidence of HCAIs is crucial for planning and implementing efficient interventions, as they are associated with a wide range of challenges. The objective of this study was to assess and update the incidence rates of HCAIs in Iran in 2023, using data from the Iranian Nosocomial Infection Surveillance (INIS) system, a nationwide hospital-based surveillance program.

Methods: The Iranian Center for Communicable Diseases Control (ICDC) evaluated data from 1,066 hospitals using the INIS software. Hospitals' trained infection control staff collected all information and entered it into the INIS. HCAIs were diagnosed based on the CDC/NHSN case definition criteria. We calculated incidence rate (per 100 admissions and per 1,000 patient-days).

Results: We reported 170,948 HCAIs among 11,043,373 hospitalized patients, with an incidence rate of 4.95 per 1,000 patient-days, and the crude mortality rate of 19.85%. Looking at the relative frequencies, Pneumonia was the most frequent infection (28.32%), followed by urinary tract infections (UTIs) (26.6%), and surgical site infections (SSIs) (21.85%). HCAI rates were highest in intensive care units (ICUs), transplant wards, and burn units, with major surgeries like cardiovascular, neurosurgeries, and orthopedics having the highest SSI rates. The most common microorganisms were Klebsiella spp. (16.56%) and E. coli (14.6%), with high proportions of multidrug-resistance (MDR) including MRSA (43.2%), VRE (65.24%), and KPC (74.21%).

Conclusions: This study reveals a high incidence of HCAIs in Iranian hospitals in 2023, with pneumonia, UTIs, and SSIs being most common. The high proportion of MDR pathogens underscores the need for enhanced infection control, antibiotic stewardship program, and continuous staff education to reduce HCAIs and improve patient outcomes.

Background: Air pollution is among the top five environmental risk factors for human health worldwide. However, our understanding of the physiological responses to PM₁₀ exposure over medium-term lag periods remains limited. This study aims to examine the medium-term lag-response associations-using lagging time windows of up to 21 days-between PM₁₀ exposure and all-cause mortality in Valencia and London from 2002 to 2006.

Methods: We used a time-stratified case-crossover design; building on the methodologies of Tobias et al. and Bhaskaran et al., we applied a fixed-effects conditional quasi-Poisson regression model to quantify the association between PM₁₀ exposure and all-cause mortality. We also analyzed three different temporal lag methodological models for the exposure-mortality relationships.

Results: We found distinct differences in the relative risk (RR) patterns of PM₁₀ exposure and all-cause mortality. In Valencia, the RR varied significantly, with confidence intervals that were wider than in London, where the RR remained more stable, fluctuating closely around 1. Significant associations were observed at early lag periods in both cities, consistent with Tobias et al. Notably, Valencia showed a significant peak in RR at lag 14, which was not observed in London. Subgroup analysis in Valencia also indicated delayed effects in younger populations. Scenario 3 (cumulative lag model) is conceptually closer to the cumulative progression of health risks associated with PM₁₀ exposure and produces higher RR estimates compared to Scenario 1 and 2.

Conclusions: This study highlights the critical importance of addressing medium-term lag-response associations and methodological variations in environmental epidemiology. The findings have important clinical and public health implications and offer insights for risk assessment, healthcare planning, and the development of policies to mitigate the health impacts of PM₁₀ exposure.

Background: Corneal dystrophies are inherited disorders that can lead to significant visual impairment and often require surgical intervention in advanced stages. Fuchs endothelial corneal dystrophy (FECD) is the most frequently diagnosed type in Western countries and remains a leading global indication for corneal transplantation. In contrast, non-Fuchs dystrophies represent a diverse group of less common entities, each with distinct clinical features, surgical considerations, and regional variations in incidence and management. Despite their relevance, long-term data on the full spectrum of corneal dystrophies remain scarce. This study aimed to evaluate the distribution and temporal trends in dystrophy types and associated surgical procedures over eight decades at a tertiary referral center in Germany.

Methods: This retrospective analysis included 3 827 histopathologically confirmed corneal dystrophy specimens identified from an archive of 58 150 ophthalmic specimens collected between 1945 and 2024. Extracted data included dystrophy type, patient age at surgery, sex assigned at birth and associated surgical procedures. Distribution and temporal trends were analyzed descriptively.

Results: FECD accounted for 90.3% (n = 3 455) of all cases, with a more than 15-fold increase in annual cases between 2003 and 2024. Its surgical management transitioned from exclusive use of penetrating keratoplasty (PKP) to posterior lamellar keratoplasty in over 99% of cases by 2024. Among non-Fuchs dystrophies (n = 372), granular (21.2%), macular (17.5%), and lattice dystrophy (17.2%) were most frequent. These exhibited greater surgical variability, reflecting their heterogeneity across 21 non-Fuchs dystrophy types in this study. Stromal and epithelial-stromal dystrophies were predominantly managed with PKP, whereas superficial epithelial and basement membrane dystrophies were increasingly treated with phototherapeutic or manual superficial keratectomy. Limbo-keratoplasty was introduced in the early 2000s for recurrent subepithelial and epithelial-stromal types.

Conclusion: This study provides unique insights into the type distribution and surgical management of corneal dystrophies over eight decades in a German center, encompassing nearly all IC3D-classified entities. The marked increase in FECD specimen numbers and the shift toward lamellar keratoplasty reflect evolving clinical practices and rising demand on corneal transplantation services. The broader clinical spectrum and procedural diversity among non-Fuchs dystrophies underscore the ongoing need for pathology-specific management strategies tailored to population-specific needs.