IntroductionTransmission of COVID-19 within families and close contacts accounts for the majority of epidemic growth. Community mask wearing, hand washing and social distancing are thought to be effective but there is little evidence to inform or support community members on COVID-19 risk reduction within families.MethodsA retrospective cohort study of 335 people in 124 families and with at least one laboratory confirmed COVID-19 case was conducted from 28 February to 27 March 2020, in Beijing, China. The outcome of interest was secondary transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within the family. Characteristics and practices of primary cases, of well family contacts and household hygiene practices were analysed as predictors of secondary transmission.ResultsThe secondary attack rate in families was 23.0% (77/335). Face mask use by the primary case and family contacts before the primary case developed symptoms was 79% effective in reducing transmission (OR=0.21, 95% CI 0.06 to 0.79). Daily use of chlorine or ethanol based disinfectant in households was 77% effective (OR=0.23, 95% CI 0.07 to 0.84). Wearing a mask after illness onset of the primary case was not significantly protective. The risk of household transmission was 18 times higher with frequent daily close contact with the primary case (OR=18.26, 95% CI 3.93 to 84.79), and four times higher if the primary case had diarrhoea (OR=4.10, 95% CI 1.08 to 15.60). Household crowding was not significant.ConclusionThe study confirms the highest risk of transmission prior to symptom onset, and provides the first evidence of the effectiveness of mask use, disinfection and social distancing in preventing COVID-19. We also found evidence of faecal transmission. This can inform guidelines for community prevention in settings of intense COVID-19 epidemics.

BackgroundDyslipidemia is a key independent modifiable risk factor for Cardiovascular Disease, which is a leading contributor to morbidity and mortality in most developed and developing countries. This study was designed to investigate the current epidemiological features of dyslipidemia among adults in rural China.MethodsBetween January 2013 and August 2013, we conducted a cross-sectional study involving 11,956 subjects with age ≥35 years in a general Chinese population. Permanent residents of the population were invited to participate in the study and the response rate was at 85.3%. Dyslipidemia was identified based on serum lipids levels following the standards proposed by the National Cholesterol Education Program Adult Treatment Panel III. Multivariate logistic regression analysis was used to evaluate the associated risk factors for dyslipidemia.ResultsWithin the study population, 16.4% had high TC, 13.8% had low HDL-C, 7.6% had high LDL-C, and 17.3% had high TG concentrations. Prevalence of lipid abnormality (including borderline dyslipidemia and dyslipidemia) was 47.8%, 13.8%, 25.7% and 30.7% for TC, HDL-C, LDL-C and TG, respectively. Detailed analysis indicated that 36.9% of this population had at least one type of dyslipidemia and 64.4% had at least one type of abnormal lipid concentration. Thus, this study observed an alarmingly higher prevalence of lipid abnormality, in a relatively large population, compared to previous studies. Further, we determined that not all of the risk factors studied, including age, gender, hypertension, diabetes mellitus, obesity, smoking, drinking, education level, marital status, and family income, influenced dyslipidemia to the same extent.ConclusionsOur present study, in a population of 11,956 adults in Liaoning Providence, demonstrated a very high prevalence of dyslipidemia, which represented an alarming rise since the publication of our previous study and other similar studies around the world, which report lower levels. We also examined various risk factors for dyslipidemia, many of which are modifiable risk factors for Cardiovascular Disease (CVD), to provide a comprehensive view that will help in designing strategies to slow the rapid spread and promote effective measures to treat dyslipidemia. Our ultimate goal is to prevent the increasing prevalence of lipid abnormality and reduce the burden of CVD in rural China.

The increasing trend of hyperuricemia in urban areas of China has been noted in the past decade. However, the prevalence of hyperuricemia in rural China has not been extensively investigated. We aimed to estimate the prevalence and risk factors of hyperuricemia and the associated comorbidities in rural Northeast China. This survey was conducted from July 2012 to August 2013. In this study, a total of 11,576 residents from the rural Northeast China were randomly selected and examined. Hyperuricemia was defined as serum uric acid ≥416 μmol/l in men and ≥357 μmol/l in women. Data regarding the demographic and lifestyle characteristics and the blood biochemical indexes of these participants were collected by well-trained personnel. The prevalence of hyperuricemia was 10.9 % and was more prevalent in men than in women (15.0 vs. 7.3 %, P < 0.001). Multivariate logistic regression models revealed that besides age, hyperuricemia in men was associated with ethnic minority [OR (95 %): 0.683 (0.472,0.989)], physical activity [moderate, OR (95 %): 0.716 (0.596,0.859); high, OR (95 %): 0.527 (0.354,0.786)], current smoking [OR(95 %):1.380 (1.179,1.616)], and current drinking [OR(95 %):0.705 (0.603,0.825)], while in women was only associated with ethnic minority [OR(95 %):0.485 (0.262,0.896)]. After adjusting for possible confounders, hyperuricemia was related to different subtypes of cardiometabolic comorbidities in both gender like abdominal obesity, general obesity, hypertriglyceridemia, hypertension, hypercholesterolemia, and low HDL-C. Besides, in women only, hyperuricemia was related to diabetes and high LDL-C. Hyperuricemia was common among residents living in rural Northeast China especially among men. Ethnic minority, physical activity, current smoking, and drinking contributed to hyperuricemia in this population.