Crucial control measures to contain China's first Delta variant outbreak.

The SARS-CoV-2 B.1.617.2 (Delta) variant flared up in late May in Guangzhou, China. Transmission characteristics of Delta variant were analysed for 153 confirmed cases and two complete transmission chains with seven generations were fully presented. A rapid transmission occurred in five generations within 10 days. The basic reproduction number (R0) was 3.60 (95% confidence interval: 2.50-5.30). After redefining the concept of close contact, the proportion of confirmed cases discovered from close contacts increased from 43% to 100%. With the usage of a yellow health code, the potential exposed individuals were self-motivated to take a nucleic acid test and regained public access with a negative testing result. Facing the massive requirement of screening, novel facilities like makeshift inflatable laboratories were promptly set up as a vital supplement and 17 cases were found, with 1 pre-symptomatic. The dynamic adjustment of these three interventions resulted in the decline of Rt from 5.00 to 1.00 within 9 days. By breaking the transmission chain and eliminating the transmission source through extending the scope of the close-contact tracing, health-code usage and mass testing, the Guangzhou Delta epidemic was effectively contained.

Epidemiology of herpes zoster among adults aged 50 and above in Guangdong, China.

Herpes zoster (HZ) exists widely in China and most cases occur among old people, but no epidemiology information of HZ was available. We aimed to investigate the epidemiology characteristics of HZ among adults aged 50 and over in Guangdong, China. A total of 34 counties/districts were randomly selected in Guangdong, and 7149 residents aged 50 and over were investigated by local CDC professionals using accidental sampling method. There were 247 respondents having had HZ before; the lifetime prevalence of HZ among people aged 50 and above in study area was 3.46%. The prevalence in females was higher than that in males. Pearl River Delta had the highest prevalence (5.29%), while Northern Guangdong had the lowest (1.87%). The annual incidence in the year 2013, 2012 and 2011 was 5.8, 3.4 and 4.1 per 1000 person-years, respectively. Detailed investigation of HZ cases showed that all cases meted the definition of HZ and had at least 1 typical symptom. 40% cases had suffered post-herpetic neuralgia. 75.9% cases had sought aid from hospital and 9.1% of them had been hospitalized. People who sought aid from hospital had more serious level of neuralgia. The epidemiology features of HZ in Guangdong were consistent with the current findings in other countries. The results of this study can provide baseline epidemiology information of HZ for further studies.

Impact of dysglycemia, body mass index, and waist-to-hip ratio on the prevalence of systemic hypertension in a lean Chinese population.

The purpose of this study was to explore whether dysglycemia, and/or an increased body mass index, and/or an increased waist/hip ratio increased the risk of hypertension in a lean population of South China. The association among dysglycemia, obesity, and hypertension has been well documented in Western populations. A stratified cluster sampling method was used according to the National Diabetes Mellitus Epidemiology Survey Program in 1998. Blood pressure, fasting plasma glucose, and plasma glucose were measured 2 hours after 75-g oral glucose consumption using the enzymatic method in the morning. Body height, weight, and waist and hip measurements were also collected for the survey. The criteria for the diagnosis of hypertension and diabetes mellitus, including impaired glucose tolerance (IGT), were those published by the World Health Organization in 1999. A total of 11,402 participants were included in the investigation (5,195 men and 6,207 women; age 20 to 74 years). A total of 1,775 cases of hypertension were confirmed in the survey. The prevalence of hypertension was significantly higher in those with diabetes mellitus than in those with a normal blood glucose level, in those with IGT than in those with normal glucose tolerance test findings, and in obese participants than in those with a normal weight (45.5% vs 14.4%, 32.2% vs 14.5%, and 20.6% vs 12.1%, respectively). Multiple logistic regression analysis indicated that age and gender-adjusted odds ratio of hypertension was 2.24 (95% confidence interval 1.88 to 2.68) with IGT compared with those without IGT. The odds ratio for hypertension associated with an increased body mass index and waist/hip ratio was 1.19 (95% confidence interval 1.17 to 1.21) and 1.08 (95% confidence interval 1.07 to 1.09), respectively. In conclusion, the data from an epidemiologic study in South China demonstrated that dysglycemia and increased body mass index and/or waist/hip ratio increase the risk of hypertension even in a lean Chinese population.

[Study on the epidemiological characteristics of overweight and obesity among population aged eighteen and over in Guangdong Province in 2002].

OBJECTIVE: To describe the epidemiological characteristics of overweight and obesity among people aged 18 and over in Guangdong province in 2002, and to identify the populations and regions under high risk. METHODS: Cross-sectional survey was used through sampling on multi-stage randomized clusters. Data of socialeconomic status were collected by face-to-face interview. Data on weight and height was obtained through physical check-ups. RESULTS: A sample size of 15 130 people and the mean body mass index (BMI) was 22.03 +/- 3.38 with no significant difference between males and females. However the significant difference was seen between cities and rural areas. The crude prevalence rate of overweight and obesity were 16.8% and 1.8%, and the age-adjusted rate were 15.0% and 1.7%, respectively. The crude rate of overweight in cities (24.8%) and males (17.5%) were higher than that in rural areas (9.4%) and females (16.2%). The crude rate of obesity in cities was seen higher than that in the rural areas, but not significantly different between females and males. The results of logistic regression analysis showed that the major risk factors influencing overweight would include household income, age, gender, smoking habits, physical exercises and location of residence. CONCLUSION: About one sixth of the citizens in Guangdong province were considered to be overweighted and obesive had become an important public health problem. Integrated measures must be taken for prevention and control.