ObjectiveTo explore the association of Breteau index（BI）, imported cases, and meteorological factors with local epidemic of dengue fever, so as to propose early warning thresholds.MethodsGuangzhou was selected as study site and years 2002-2013, as study period. The classification and regression trees model was applied to analyze the associations between the predictive variables including average monthly BI, average monthly imported cases, average monthly temperature,monthly maximum temperature,monthly minimum temperature,average monthly temperature difference,monthly total rainfall, average monthly rainfall,average monthly relative humidity, average monthly atmospheric pressure, and the outcome variables consisting of local dengue whether or not occur and the number of indigenous cases at month level separately.ResultsA total of 3 996dengue cases, including 3 769 (94.32%) indigenous cases and 227 (5.68%) imported cases, were reported in 44 (30.56% of 144) months during the period of 2002 - 2013. In the classification tree model for whether or not the local cases of dengue fever would appear, the number of imported cases, BI, maximum temperature and minimum temperature of the months were eventually incorporated. When the average monthly imported cases were ≥3.5, the RR was 3.00 (2.22 - 4.05) indicating the risk for local cases to occur was the greatest; when the average monthly imported cases were <3.5 and average monthly BI was ≥8.59, the RR was 2.40 (1.62 - 3.55); when inputting the average monthly imported cases <3.5, average monthly BI <8.59, monthly maximum temperature ≥31.41 ℃, and monthly minimum temperature <24.90 ℃, the RR was 2.18 (1.29 - 3.68). In the regression tree model for the severity of indigenous cases, average monthly BI, average monthly temperature, and average monthly imported cases were incorporated. When the average monthly BI was ≥5.29 and average monthly temperature was <27.04 ℃, the RR was the highest (5.11，3.36 - 7.77) ; when the average monthly temperature was ≥27.04 ℃ and everage monthly BI was ≥9.16, the RR was 3.20 (2.06 - 4.96); when the average monthly BI was <5.29 and the average monthly imported cases were ≥3.5, the RR was 2.22 (1.40 - 3.53).ConclusionThe everage monthly imported cases and everage monthly BI are most important two factors for whether or not local dengue cases would appear, and the average monthly BI and monthly average temperature, most important two factors for the severity of local dengue epidemic.

ObjectiveTo analyze the survival time and related factors of HIV/AIDS in Lu’an City.MethodsData of HIV/AIDS report cards, supplementary cards, case followup tables, medical records and necessary supplementary investigation information of Luan City from 1999 to March 2014 were collected from Chinese national HIV/AIDS comprehensive control and prevention information system, including general demographic characteristics (gender, age, occupation, marital status, educational level), route of infection, stage of disease and CD4 levels at confirmed diagnosis, highly active antiretroviral therapy (HAART) and followup outcome. Life table method was applied to calculate the survival rate. The survival status of the patients was described and the related factors affecting survival status of patients with HIV/AIDS were analyzed by univariate and multivariate logistic regressions.ResultsA total of 661 cases of HIV/AIDS were reported. At the end point of the survey, 540 cases of HIV/AIDS survived and finished the followup, with a survival rate of 81.69%; 121 cases died of AIDS and its associated complications with a death rate of 18.30%. Among them, 512 were males and 149, females; their ages ranged from 1 to 81 years old, with a median age of 34.5 years. The survival rate of HIV/AIDS cases at 1, 3, and 5 years were 83.00%, 80.00%, and 75.00%, respectively. The AIDS related mortality was 6.70/1 000 personmonths. At the end point of the investigation, the 12year survival rate of HIV/AIDS was 67.00%. In the Cox proportional hazard model, compared with the cases of HIV/AIDS with CD4 counts fewer than 100 cells/mm3 at diagnosis, the risk of death was decreased from 0.24 to 0.03 time in the cases with CD4 counts equal or greater than 100 cells/mm 3.The risk of death for cases not receiving HAART was 16.94 times that for cases receiving HAART; compared with the cases aged 60 years and older, the risk of death was decreased from 0.47 to 0.29 time for every 10 years of age in the cases aged 18 years and above at confirmed diagnosis. The risk of death for females was 1.64 times that for males.ConclusionCD4 level and age at confirmed diagnosis and gender influenced the survival time of people living with HIV/AIDS. HAART was one of the effective means to prolong the survival time of AIDS patients; therefore, the coverage of HAART should be further expanded.

ObjectiveTo investigate prevalence of selfreported lipoprotein metabolic disorder and related risk factors among residents aged ≥15 years old in Guangzhou so as to provide a scientific basis for early prevention and intervention of cardiovascular and cerebrovascular diseases.MethodsUsing multistage cluster random sampling method, residents aged 15 years and older were selected from 9 600 households in Guangzhou for questionnaire survey and physical examination. Contents of the questionnaire included the general information, daily life, lipoprotein metabolic disorder, and other common chronic diseases. Items of physical examination included height, weight, waist, hip circumference, and blood pressure. Univariate and multivariate logistic regressions were used to analyze the risk factors of the diseases among different groups.ResultsA total of 23 994 residents aged 15 years and older were investigated. The male to female ratio was 1∶1.03. They were concentrated in the group aged 35-44 years (20.3%); their education levels were mainly junior, senior or secondary school (54.2%) and the occupation was mainly the unemployed(21.7%). The total prevalence of selfreported lipoprotein metabolic disorder was 1.47% (352/23 994). Multivariate logistic regression analysis showed that age 55-65 years (OR=1.34), high school/technical secondary school and college or above (OR=2.37, 3.17), retirees (OR=2.65), newly or ever diagnosed hypertension (OR=1.54, 5.26), diabetes mellitus (OR=2.33), and abnormal BMI (OR=2.78-10.33) were independent risk factors for lipoprotein metabolic disorder, while age groups at 25-34, 35-44 years old (OR=0.13,0.46) and fruit intake ≥200 g/d (OR=0.77) were protective factors for lipoprotein metabolic disorder (P<0.05 or P＜0.01).ConclusionThe total prevalence of selfreported lipoprotein metabolic disorder was low in Guangzhou. Each community should strengthen the high risk population screening and improve the awareness of the disease. Reasonable dietary pattern, weight control, and prevention of hypertension and diabetes were important measures to prevent and control lipoprotein metabolic disorder.

ObjectiveTo investigate the sleep quality and related factors among people aged 65 and above in rural mountainous area of Yiling District, Yichang City, so as to provide evidence for intervention measures.MethodsA stratified cluster sampling method was used to select five mountainous towns of Yiling District, Yichang City. Six administrative villages were randomly selected in each town and residents aged 65 and above were chosen from the selected villages to participate in the survey. The survey content included basic information, personal life (including sleep, physical activity, life satisfaction, family relationships, etc.), and health status. Univariate and multivariate logistic regressions were used to analyze the sleep quality and its influencing factors.ResultsA total of 4 002 residents aged 65 - 96 years old were investigated and their average age was (73.34±6.01) years. The male to female ratio was 0.94∶1. Of all the participants, 58.5% were aged 65 to 74 years, 90.7% had the educational level at primary school, 68.2% were single, and 65.1% had an annual household income less than 10 000 Yuan. The selfrated poor sleep quality rate was 55.4% (2 216/4 002), the average sleep time was (7.94±2.08) h/d, and 25.3% of them (1 013/4 002) had sleep time <7.0 h / d. Multivariate logistic regression analysis showed that, compared with the female, aged ≥75 years, unsatisfactory to life, poor family relationship, and lonely elderly, the possibility of poor sleep quality was less for the male, aged 65 - 74 years, satisfaction to life, good family relationship, and unlonely elderly (OR=0.692, 0.855, 0.550, 0.761, 0.595, respectively). Compared with the educational level at junior high school and above, in marriage, and no chronic diseases, the persons with the education level at primary school and below, single,and with chronic diseases were more likely to have poor sleep quality(OR=1.318,1.230,1.453,respectively) .ConclusionPeople aged 65 years and older in Yiling rural mountainous area had big sleep problem and intervention measures should be taken to improve the status .

ObjectiveTo study the prevalence of depression and influencing factors among middle school students in Shanwei City.MethodsStudents were randomly selected from 12 middle schools in Shanwei City by using a twostage stratified cluster sampling method for an anonymous selfreport questionnaire survey. General demographic characteristics, sleep quality, depression, and drug abuse were evaluated by a selfdesigned questionnaire of adolescents' health knowledge, Pittsburgh sleep quality index scale, and the Center for Epidemiological Studies Depression Scale. Data were analyzed using univariate and multivariate logistic regressions.ResultsA total of 3 489 questionnaires were distributed and 3 042 were valid, with an effective response rate of 87.2% (3 042/3 489). The average age of the participants were (16.06 ± 1.83) years.The male to female ratio was 1∶0.94. The average score of the depression scale in the students was (15.23±9.37), and 307 students had the depression symptoms (depression rating score > 28). Depressive symptom detection rate of the students was 10.1%. The rate of drug abuse was 0.8%. Multivariate analysis showed that female, Grade 12, study pressure, family relationships not good and with much conflicts, average and poor relationship with peers, average and poor sleep quality, and drug abuse were risk factors for adolescent depressive symptoms (ORs: 2.10, 1.97, 2.60, 1.77, 3.59, 2.17, 6.55, 7.27, 21.75, 1.46).ConclusionThe middle school students in Shanwei City had certain depressive symptoms. Special attention should be paid to the Grade 12 students with tremendous learning pressure. Mental health education and timely mediating conflicts among students should be conducted to improve their sleep quality and adjust depressed mood to prevent the occurrence of depression.

ObjectiveTo investigate the status of eyesight dysfunction (ED) and analyze the visionrelated behaviors between migrant and local students in primary and middle schools in Shenzhen.MethodsA schoolbased crosssectional, stratifiedcluster sampling was conducted in 6 public schools and 6 migrant children schools in Baoan District, Shenzhen. Students from the private migrant primary schools and the urban public schools in grades 3 to 9 were selected. All eligible participants finished questionnaires and implemented eye examination. Multilevel logistic regression models were conducted to analyze data.ResultsA total of 9 519 students were surveyed and their average age was (11.98 ± 1.95) years. Of them, 5 442 were male and 4 077, female; 4 428 (46.5%) were migrant and 5 091 (53.5%), local. There was statistical significance between the average ages of the tow group students (P< 0.01). Prevalence of ED was 57.24%（2 914/5 091）for the local students and 50.52% for the migrants（2 237/4 428）(P<0.01). The multilevel model analysis showed that the incidences of doing homework, reading books for over 1 h/d, continuously reading/writing for over 30 min, studying in classroom during the breaks for over 3 t/d, sleeping time less than 9 h/d and doing physical activities less than 1 h/d on workdays in migrant group were lower than the counterparts (OR: 0 .44, 0.49, 0.55, 0.60, 0.62, 0.55, 0.69). The incidences of watching TV/operating computer/playing mobile phone for over 1 h/d, continuously playing mobile phone for over 30 min, resting in classroom for less than 3 t/d,doing eye relaxation exercise less than 3 t/d and sleeping time less than 9 h/d on weekends and holidays among migrants were higher than the locals (OR: 1.34, 1.20, 1.34, 1.14, 1.21, 1.17, 3.52). ConclusionLocal students have worse vision than migrant ones, which indicates that specific measures should be addressed to the targeted group for prevention and control of ED.

ObjectiveTo analyze the epidemiological features of hepatitis C in Guangdong Province in recent years so as to provide strategies for control and prevention of hepatitis C. MethodsData of hepatitis C cases were downloaded from China information system for disease control and prevention and then analyzed using descriptive epidemiological methods. ResultsA total of 107 316 cases of hepatitis C were reported from 2005 to 2013, including 107 deaths. The number of reported cases increased from 3 784 in 2005 to 18 413 in 2013, with an average annual growth rate of 22.9%. Top six cities with most reported cases were Guangzhou (23 107), Foshan (13 794), Shenzhen (10 529), Dongguan (8 408), Zhongshan (5 478), and Maoming (5 005), which accounted for 61.8% of total reported cases. There were 72 855 males and 34 461 females; the malefemale ratio of the cumulative cases was 2.1∶1. The cases were mainly concentrated in the age group between 20 and 49 years (77 798 cases, 72.5% of the total cases). The occupations of the cases were mainly the housework and unemployed (23 131, 21.6%), followed by peasants, herders, and fishermen (19 831, 18.5%), workers (12 428, 11.6%), and children and students (3 574, 3.3%).ConclusionThe reported cases of hepatitis C have increased annually in Guangdong Province from 2005 to 2013, indicating there were unsafe behaviors in medical practice in Guangdong. The supervision of unsafe behaviors in medical practice should be strengthened.