Epidemiology and Infection最新文献

Investigating risk factors for mpox's infectious period is vital for preventing this emerging disease, yet evidence remains scarce. This study aimed to identify risk factors associated with the duration of mpox infectiousness among mpox cases in Vietnam. The primary outcome was the duration of the mpox infectiousness, defined between symptom onset and the first negative test result for the mpox virus. Fine and Gray's regression models were employed to assess the associations between the infectious period and several risk factors while accounting for competing risks of death by mpox. Most mpox cases recovered within 30 days. Patients with HIV or treated at multiple facilities for mpox had lower incidence rates of cleared infection compared to those who were HIV-negative or treated at a single facility. In regression models, patients with mpox symptoms of rash or mucosal lesions (sub-distribution hazard ratios = 0.62, 95% confidence interval = 0.46-0.83), ulcers (0.57, 0.41-0.80), or fever (0.62, 0.46-0.83) had significantly prolonged infectious periods than those without such symptoms. Our findings provided insights for managing mpox cases, especially those vulnerable to prolonged infectious periods in settings with sporadic cases reported.

The Alpha, Delta, and Omicron variants of the SARS-CoV-2 virus have been deemed as variants of concern (VOCs) by the WHO due to their increased transmissibility, severity of illness, and resilience against treatments. Geographically tracking the spread of these variants can help us implement effective control measures. RNA from 8,154 SARS-CoV-2 positive nasal swab samples from a Central Texas hospital collected between March 2020 and April 2023 were sequenced in Temple, TX. Global and U.S. sequencing metadata was obtained from the GISAID database on 3 April 2023. Using sequencing metadata, the growth rate of Alpha, Delta, and the first subvariant of Omicron (BA.1) were obtained as 0.27, 0.3, and 1.08 each. The average time in days to penetrate the US for Alpha, Delta, and Omicron were 269.2, 326.2, and 27.3 days, respectively. Viral sequencing data can be a useful tool to examine the spread of viruses. Each emerging SARS-CoV-2 variant penetrated cities more rapidly as the pandemic progressed. With a high logarithmic growth rate, the Omicron variant penetrated the US more rapidly as the pandemic progressed.

Dengue virus (DENV) remains a pressing global health challenge, primarily transmitted by Aedes aegypti mosquitoes. This review synthesizes current knowledge on the biological, environmental, and molecular factors influencing DENV transmission, drawing upon 120 peer-reviewed studies. The narrative analysis highlights the mosquito’s vector competence, shaped by genetic variability, midgut barriers, and immune responses. Environmental drivers particularly temperature, humidity, and urbanization emerge as critical determinants of transmission dynamics. A meta-analysis of 30 studies reveals a strong positive correlation (r = 0.85, p < 0.01) between temperature (25 °C–30 °C) and transmission efficiency. Proteomic studies further detail molecular interactions facilitating viral entry and replication. Although novel interventions such as Wolbachia-based biocontrol and genetic modification show promise, context-specific implementation remains challenging, especially in low-resource settings. Key research gaps include the impact of climate change, co-infections with other arboviruses, and the long-term efficacy of vector control innovations. Prioritizing interdisciplinary approaches and adapting strategies to local contexts are vital to reducing the dengue burden and informing future public health responses.

Hepatitis B virus vaccination is currently recommended in Australia for adults at an increased risk of acquiring infection or at high risk of complications from infection. This retrospective cohort study used data from an Australian sentinel surveillance system to assess the proportion of individuals who had a recorded test that indicated being susceptible to hepatitis B infection in six priority populations, as well as the proportion who were then subsequently vaccinated within six months of being identified as susceptible. Priority populations included in this analysis were people born overseas in a hepatitis B endemic country, people living with HIV, people with a recent hepatitis C infection, gay, bisexual and other men who have sex with men, people who have ever injected drugs, and sex workers. Results of the study found that in the overall cohort of 43,335 individuals, 14,140 (33%) were identified as susceptible to hepatitis B, and 5,255 (37%) were subsequently vaccinated. Between 26% and 33% of individuals from priority populations were identified as susceptible to hepatitis B infection, and the proportion of these subsequently vaccinated within six months was between 28% and 42% across the groups. These findings suggest further efforts are needed to increase the identification and subsequent vaccination of susceptible individuals among priority populations recommended for hepatitis B vaccination, including among people who are already engaged in hepatitis B care.

Contact tracing is an effective public health policy to put the fast-spreading epidemic under control. The government tracks the contacts of confirmed SARS-CoV-2 cases, recommends testing, encourages self-quarantine, and monitors symptoms of contacts. In developing and less-developed countries with limited resources for widespread SARS-CoV-2 testing, it remains essential to identify and quarantine positive contacts to control outbreaks. Therefore, analysing recall and precision when implementing testing policies for these contacts is necessary. We analysed a contact tracing dataset from a cohort of 827 index patients infected with SARS-CoV-2 and their 14814 close contacts from Jan 2020 to July 2020 in a province in eastern China. We constructed a network from the data and used a Graph Convolutional Network to predict each contact's infection status. To the best of our knowledge, this is the first method to use population-based contact tracing data for predicting the infection status using graph neural networks. Despite limited information, our model achieves competitive Area Under the Receiver Operating Characteristic Curve (ROC AUC) compared to hospital-onset scenarios. Based on the risk scores, we propose several contact testing policy adaptations that balance resource efficiency and effective pandemic control.

Antimicrobial resistance (AMR) in intensive care units (ICUs) is a critical issue, which has been exacerbated by the coronavirus disease 2019 (COVID-19) pandemic. This study investigated AMR prevalence and its associated factors among ICU patients in two Vietnamese hospitals from January 2020 to June 2022. Electronic medical records of 1,296 patients with 2,432 non-duplicate bacterial isolates were collected in Phu Tho Hospital (Northern, rural, non-COVID-19 treatment) and 175 Hospital (Southern, urban, COVID-19 treatment centre). Antibiotic susceptibility testing was conducted using VITEK2, BD Phoenix 100, and disk diffusion methods. Logistic regression with 1,000 bootstrap resampling and cross-validation was used to examine factors linked to AMR. Results revealed Acinetobacter spp. (27.5%) as leading strains in Phu Tho Hospital, while Klebsiella spp. (28.0%) predominated in 175 Hospital, except during 2021when Acinetobacter spp. reached the peak. Alarmingly, Acinetobacter spp., Klebsiella spp., and Pseudomonas aeruginosa demonstrated the highest AMR rates and multidrug resistance rates (83.8%-95.8%) in both hospitals. Resistance to cephalosporins, carbapenems, and fluoroquinolones ranged from 75% to 100%. Significant associated factors included age, sex, location, initial admission diagnosis, and bacterial isolation month. This study highlights the urgent need for controlling AMR in ICUs during the pandemic.

Mosquito-borne California serogroup orthobunyaviruses Inkoo (INKV) and Chatanga (CHATV) are known to be endemic in Finland with a high seroprevalence. We developed a novel multiplexed reverse transcription quantitative polymerase chain reaction method for discriminating between the INKV and CHATV. This assay was used along with traditional serological tests to study a set of summertime patients during the years 2021, 2023, and 2024 to assess the epidemiology and prevalence of acute INKV and CHATV infections in Finland. Altogether, 1470 samples were screened, and there were 16 patients who had an acute infection based on serological findings and/or nucleic acid test. The orthobunyavirus-IgG seroprevalences were 18% (2021), 20% (2023), and 30% (2024), being lower than that in studies from 20 years ago. Neutralization tests were carried out, and all but one acute case had more than four-fold higher titre to INVK vs. CHATV, indicating specificity to INKV infection. The results suggest that epidemiology has changed from previous studies, and INKV should be considered a causative agent of summertime infections in Finland. The symptom diversity in mild disease outcomes should be studied to guide orthobunyavirus recognition by clinicians. The use of molecular assay discriminating INKV and CHATV aids in understanding disease associations.

Tuberculosis (TB) remains a significant public health concern in China. Using data from the Global Burden of Disease (GBD) study 2021, we analyzed trends in age-standardized incidence rate (ASIR), prevalence rate (ASPR), mortality rate (ASMR), and disability-adjusted life years (DALYs) for TB from 1990 to 2021. Over this period, HIV-negative TB showed a marked decline in ASIR (AAPC = -2.34%, 95% CI: -2.39, -2.28) and ASMR (AAPC = -0.56%, 95% CI: -0.62, -0.59). Specifically, drug-susceptible TB (DS-TB) showed reductions in both ASIR and ASMR, while multidrug-resistant TB (MDR-TB) showed slight decreases. Conversely, extensively drug-resistant TB (XDR-TB) exhibited upward trends in both ASIR and ASMR. TB co-infected with HIV (HIV-DS-TB, HIV-MDR-TB, HIV-XDR-TB) showed increasing trends in recent years. The analysis also found an inverse correlation between ASIRs and ASMRs for HIV-negative TB and the Socio-Demographic Index (SDI). Projections from 2022 to 2035 suggest continued increases in ASIR and ASMR for XDR-TB, HIV-DS-TB, HIV-MDR-TB, and HIV-XDR-TB. The rising burden of XDR-TB and HIV-TB co-infections presents ongoing challenges for TB control in China. Targeted prevention and control strategies are urgently needed to mitigate this burden and further reduce TB-related morbidity and mortality.

This study analyzed standardized excess mortality due to specific causes during the Covid-19 pandemic across 33 European countries, using Eurostat data (2016-2021) and Our World in Data databases. Causes included circulatory and respiratory diseases, neoplasms, transport accidents, and "other" causes (e.g., diabetes, dementia, ill-defined conditions). Additional variables such as vaccination rates, economic and health indicators, demographics, and government stringency measures were also examined. Key findings include: (1) Most European countries (excluding Central and Eastern Europe), recorded lower than expected excess mortality from circulatory and respiratory diseases, neoplasms, and transport accidents. Ireland had the lowest excess respiratory mortality in both 2020 and 2021; (2) Croatia, Cyprus, Malta, and Turkey showed significant positive excess mortality from "other" causes, potentially linked to public health restrictions, with Turkey as an exception; (3) Regression analysis found that higher human development index and vaccination rates were associated with lower excess mortality. Policy Implications are: (1) Statistically significant positive or negative cause-specific excess mortality may indicate future health trends; (2) The pandemic and government stringency measures negatively affected mortality from "other" causes; (3) Strengthening health system resilience, investing in digital medicine, directing aid to countries with weaker systems, and supporting disadvantaged groups are key recommendations.

Cryptosporidium parvum is a well-established cause of gastrointestinal illness in both humans and animals and often causes outbreaks at animal contact events, despite the availability of a code of practice that provides guidance on the safe management of these events. We describe a large C. parvum outbreak following a lamb-feeding event at a commercial farm in Wales in 2024, alongside findings from a cohort study to identify high-risk exposures. Sixty-seven cases were identified, 57 were laboratory-confirmed C. parvum, with similar genotypes. Environmental investigations found a lack of adherence to established guidance. The cohort study identified 168 individuals with cryptosporidiosis-like illness from 540 exposure questionnaires (distributed via email to 790 lead bookers). Cases were more likely to have had closer contact with lambs (odds ratio (OR) kissed lambs = 2.4, 95% confidence interval (95% CI): 1.2-4.8). A multivariable analysis found cases were more likely to be under 10 years (adjusted OR (aOR) = 4.5, 95% CI: 2.0-10.0) and have had visible faeces on their person (aOR = 3.6, 95% CI: 2.1-6.2). We provide evidence that close contact at lamb-feeding events presents an increased likelihood of illness, suggesting that farms should limit animal contact at these events and that revisions to established codes of practice may be necessary. Enhancing risk awareness among farmers and visitors is needed, particularly regarding children.