No Association of COVID-19 transmission with temperature or UV radiation in Chinese cities

The COVID-19 epidemic, caused by the SARS-CoV-2 virus, has resulted in 3352 deaths in China as of April 12, 2020. This study aimed to investigate the associations between particulate matter (PM) concentrations and the case fatality rate (CFR) of COVID-19 in 49 Chinese cities, including the epicenter of Wuhan. We used the Global Moran's I to analyze spatial distribution and autocorrelation of CFRs, and then we used multivariate linear regression to analyze the associations between PM2.5 and PM10 concentrations and COVID-19 CFR. We found positive associations between PM pollution and COVID-19 CFR in cities both inside and outside Hubei Province. For every 10 μg/m3 increase in PM2.5 and PM10 concentrations, the COVID-19 CFR increased by 0.24% (0.01%-0.48%) and 0.26% (0.00%-0.51%), respectively. PM pollution distribution and its association with COVID-19 CFR suggests that exposure to such may affect COVID-19 prognosis.

Background: Chronic complications are the major outcome of type 2 diabetes mellitus progress, which reduce the quality of life of patients, incur heavy burdens to the health care system, and increase diabetic mortality. The aims of this study were to describe the prevalence of chronic complications among urban Chinese type 2 diabetic outpatients; and to analyze the associations between chronic complications and patients' demographics, diabetic related clinical characteristics. Methods: This cross-sectional hospital-based study was carried out in 4 major Chinese cities: - Shanghai, Chengdu, Beijing and Guangzhou. The survey was conducted from March to July in 2007 among 1,524 type 2 diabetic outpatients. The subjects were interviewed face-to-face by trained interviewers using a questionnaire to capture information on demographics, disease presentations and complications. All the subjects were invited to have a HbA1c test free of charge by the standardized method with Bio-Rad Variant II. Results: Of the 1,524 study subjects, 637 (41.8%) were male, and the mean age was 63.3 ± 10.2 years. At least one chronic complication was diagnosed in 792 individuals (52.0%) of the study subjects; 509 (33.4%) presented with macrovascular complications and 528 (34.7%) with microvascular complications. The prevalence of cardiovascular and cerebrovascular conditions, neuropathy, nephropathy, ocular lesions and foot disease were 30.1%, 6.8%, 17.8%, 10.7%, 14.8% and 0.8%, respectively. The prevalence of chronic complications varied between cities, and significantly increased with age and duration of diagnosed diabetes. The mean of HbA1c in diabetic patients with chronic complications was 8.2% ± 1.6% and 63.0% of the subjects with type 2 diabetes related complications had a poor glycemic control with the HbA1c > 7.5%. Conclusions: Chronic complications are highly prevalent among type 2 diabetic outpatients, the glycemic control of diabetic patients with chronic complications was poor, and future efforts should be directed at intensive blood glucose control, strengthening early diagnosis and improving case management to prevent and minimize the occurrence of complications.

Background: Limited data are available on the effectiveness of inactivated and Ad5-nCoV COVID-19 vaccines in real-world use—especially against Omicron variants in SARS-CoV-2 infection-naïve population. Methods: A matched case-control study was conducted among people aged ≥ 3 years between 2 December 2021 and 13 May 2022. Cases were SARS-CoV-2-infected individuals, individuals with severe/critical COVID-19, or COVID-19-related deaths. Controls were selected from consecutively test-negative individuals at the same time as cases were diagnosed and were exact-matched on year-of-age, gender, birthplace, illness onset date, and residential district in ratios of 1:1 with infected individuals and 4:1 with severe/critical COVID-19 and COVID-19-related death. Additionally, two subsets were constructed to analyze separate vaccine effectiveness (VE) of inactivated vaccines (subset 1) and Ad5-vectored vaccine (subset 2) against each of the three outcomes. Results: Our study included 612,597 documented SARS-CoV-2 infections, among which 1485 progressed to severe or critical illness and 568 died. Administering COVID-19 vaccines provided limited protection against SARS-CoV-2 infection across all age groups (overall VE: 16.0%, 95% CI: 15.1–17.0%) but high protection against severe/critical illness (88.6%, 85.8–90.8%) and COVID-19-related death (91.6%, 86.8–94.6%). In subset 1, inactivated vaccine showed 16.3% (15.4–17.2%) effective against infection, 88.6% (85.8–90.9%) effective against severe/critical COVIID-19, and 91.7% (86.9–94.7%) against COVID-19 death. Booster vaccination with inactivated vaccines enhanced protection against severe COVID-19 (92.7%, 90.1–94.6%) and COVID-19 death (95.9%, 91.4–98.1%). Inactivated VE against infection began to wane 12 weeks after the last dose, but two and three doses sustained high protection levels (> 80%) against severe/critical illness and death, while subset 2 showed Ad5-vectored vaccine was 13.2% (10.9–15.5%) effective against infection and 77.9% (15.6–94.2%) effective against severe/critical COVIID-19. Conclusions: Our real-world study found high and durable two- and three-dose inactivated VE against Omicron-associated severe/critical illness and death across all age groups, but lower effectiveness against Omicron infection, which reinforces the critical importance of full-series vaccination and timely booster dose administration for all eligible individuals.