Epidemiology and Infection最新文献

This study assessed the impact and cost-effectiveness of pre-exposure prophylaxis (PrEP) in reducing HIV infections and HIV-related deaths among four key populations in China: men who have sex with men (MSM). Female sex workers (FSW), people who inject drugs (PWID), and HIV-negative partners of serodiscordant couples (SDC). Decision-analytic Markov models simulated HIV transmission and progression in cohorts of 100,000 adults over 40 years under three strategies: no PrEP, daily oral PrEP, and on-demand oral PrEP evaluated nationaly and high-incidence provinces. Cost-effectiveness was measured using a willingness-to-pay threshold of US$37,653 per QALY. Across all populations, on-demand PrEP was the most cost-effective strategy. Among MSM, it was cost-effective both nationwide (ICER: $4,554/QALY) and in high-incidence provinces (ICER: $1,045-2,129/QALY), reducing new infections by 24.7%. Daily PrEP was also const-effective for MSM nationally and prevented 19.9% of infections. For FSW, on-demand PrEP was cost-effective in high-incidence provinces (ICER: $25,399-37,045/QALY), reducing infections by 21.8%-22.5%. For PWID, it was cost-effective in high-incidence provinces (ICER: $10,361-29,560/QALY), reducing infections by 15.5%-17.9%. For HIV-negative partners of SDC, on-demand PrEP was cost-effective both nationally and in high-incidence provinces, reducing infections by 24.0%. Overall, on-demand PrEP offers substantial health and economic benefits, particularly for HIV-negative partners of SDC and high-incidence regions.

This cross-sectional study investigated how care home size influences COVID-19 transmission dynamics, focusing on outbreaks in England during the second wave of COVID-19 (Wave 2; December 2020 to March 2021) and the Omicron wave (December 2021 to February 2022). Using data from the UK Health Security Agency and the Care Quality Commission, positive SARS-CoV-2 test results were matched to care home registration and occupancy data, examining outbreak trajectories in homes of varying sizes and resident age groups. The study included over 90,000 positive cases across the two waves. Small care homes (SCHs, with 10 or fewer beds), predominantly housing younger adults, showed significantly higher early positivity rates: 42% of residents were positive at outbreak detection, rising to 61% by day 7. In contrast, larger homes had early positivity rates of only 3-6%. These findings suggest that SCHs, often designed for communal living, facilitate rapid within-home transmission similar to household settings. The study concludes that outbreak control strategies in SCHs should differ from those in larger care homes, emphasizing proportionate, individualized approaches that consider resident vulnerability and minimize disruption to social support systems. These results have broader implications for managing future infectious disease outbreaks and support the development of tailored guidance based on care home size and resident demographics.

Effectiveness of nirsevimab against respiratory syncytial virus (RSV) hospitalization during the 2024/2025 season in Spain was estimated using a test-negative design (TND) and hospital-based respiratory infections surveillance data. Children born between 1 April 2024 and 31 March 2025 and hospitalized with severe respiratory infection between the start of the 2024 immunization campaign (regionally variable, between 16 September and 1 October 2024) and 31 March 2025 were systematically RT-PCR RSV-tested within 10 days of symptom onset and classified as cases if positive or controls if negative. Nirsevimab effectiveness ((1 - odds ratio) × 100) was estimated using logistic regression, adjusted for admission week, age, sex, high-risk factors, and regional RSV hospitalization rate. We included 199 cases (68.8% immunized) and 360 controls (86.4% immunized). Overall effectiveness was 65.5% (95% confidence interval: 45.2 to 78.3). Effectiveness was similar among infants born before and after the campaign start (63.6% vs. 70.4%, respectively). We found an unexpected early decrease in effectiveness with increasing time since immunization and age, albeit with wide confidence intervals for some groups. Strong age-period-cohort effects and potential sources of bias were identified, highlighting the need to further explore methodological challenges of implementing the TND in the dynamic population of newborns.

Respiratory infections trigger asthma exacerbations. Despite being less severely affected by COVID-19 than adults, the subsequent lockdowns had a great impact on children. Previous studies showed a decrease in asthma exacerbations during the COVID-19 lockdowns, but findings from secondary care settings are scarce. We aimed to elucidate the trends in frequency and characteristics of asthma exacerbations in children presenting on an emergency department (ED) of a secondary care setting before, during, and after the COVID-19 pandemic. A retrospective analysis was conducted using data from ED visits between January 2018 and November 2022 for asthma exacerbations in children. The incidence of ED visits, hospital admissions, paediatric intensive care unit (PICU) admissions, administered medication, and demographic information were compared. A total of 1121 exacerbations were reported in 670 children, of whom 476 (42%) were admitted to hospital and 44 (3.9%) required PICU admission. We observed a decrease in ED visits for asthma exacerbations during the pandemic but an increased risk in hospital admissions and PICU transfers for exacerbations. This suggests a more severe course of exacerbations. Barriers to health care and lower viral exposure may contribute to this.

Google Trends is used in research and surveillance as a proxy for community infection incidence. Signals are difficult to validate, as most surveillance biases towards severe outcomes and certain demographics.Using Winter COVID-19 Infection Study (WCIS) data in England, symptom prevalence is estimated via generalized additive model with multilevel-regression and poststratification. Symptom duration was estimated using interval censored time delay modelling, converting prevalence to incidence. Google Trends and WCIS incidence and growth rates were compared using cross-correlation.Google Trends and WCIS agreement varied by symptom and age group. The national maximum growth rate cross-correlation for sore throat was 0.81, with 90% prediction intervals of [0.69, 0.90]. Google Trends growth rates generally lagged the WCIS growth rates across symptoms (cough: -5.0 days [-8.0, 0.0], fever: -3.0 days [-6.0, 1.0], loss of smell: -9.0 days [-13, -3.0], shortness of breath: -12 days [-16, -5.0], and sore throat: -4.0 days [-5.0, -2.0]).This work shows Google Trends and community symptom incidence can align, although substantial variation between symptoms and age groups exists, underscoring utility in predicting other surveillance indicators.

Measuring waning in vaccine effectiveness (VE) is challenging due to potential depletion-of-susceptibles bias. Some SARS-CoV-2 studies excluded individuals with prior infection and adjusted for the probability of remaining uninfected. We applied this approach to assess waning influenza VE in Hong Kong during the 2012/2013 season. First, we estimated the infection risk for unvaccinated children using published serological and surveillance data. Next, we derived infection risk for vaccinated children, assuming VE against infection of 57%. Uncorrected VE from 14 to 270 days post-vaccination was estimated from hospitalized children. We calculated the rate of depletion of susceptibles given infection risk and VE corrected for depletion-of-susceptibles bias. Waning rates for uncorrected and bias-corrected VE were measured by comparing VE at day 270 versus day 14. Bias was assessed as the absolute difference between two waning rates in percentage points. Waning rate of uncorrected VE was overestimated by 5.9 percentage points or 1.3 percentage points when assessed up to day 120. Bias was substantial when assuming 80% unvaccinated, and all vaccinated children were initially uninfected, but minimal when these proportions were similar. The observed waning in 2012/2013 was unlikely due to depletion-of-susceptibles bias. Further studies across various conditions are needed to confirm our findings.

We sought to identify risk factors for coagulase-negative staphylococcal (CoNS) surgical site infection (SSI). Risk factors associated with an increased risk of CoNS SSI include male sex and asthma or COPD. Colon surgery was associated with a reduced risk of CoNS SSI.

In this study, HFRS data were obtained from China CDC and ECDC, while monthly meteorological data and GDP were extracted from the National Bureau of Statistics of China website. Descriptive epidemiology, time series decomposition, and spatial autocorrelation analyses were employed to evaluate HFRS incidence patterns. A spatial panel data model was used to estimate the effects of meteorological and socio-economic variables on HFRS incidence. The average annual incidence rate of HFRS was 0.90/100000 in China, compared to 29.3/100000 in Finland. The incidence level in China was comparable to that in Belgium and the EU/EEA (excluding the UK), the high-incidence age group was 45-64 years, which was similar to Finland and the EU/EEA. HFRS in China exhibited marked seasonality. Three north-eastern provinces, Shaanxi, Shandong, and Jiangxi reported higher incidence rates. After adjusting for spatial individual effects and spatial autocorrelation, HFRS incidence was negatively associated with precipitation during the same period, per capita GDP showed no significant effect on HFRS incidence. Continued surveillance and prevention of HFRS remain necessary in China, particularly in Shaanxi. Additional disease prevention and control efforts should be directed towards individuals aged 45-64 years during the high-risk period from October to December.