Objective To analyze the incidence trends and epidemic characteristics of scarlet fever in Guangdong Province during 1950-2011 and provide evidence for preventing and controlling scarlet fever. Methods Descriptive statistical analysis was performed on epidemiological data of scarlet fever during 1950-2011 obtained from Guangdong Diseases Reporting Information System. Results A total of 15 581 cases were reported to the Guangdong Notifiable Disease Database during 1950-2011 with the annual incidence ranging between 0 to 49.00/100 000. There are four epidemic stages: Distributed Period (1950-1973, the average annual incidence was 0.12/100 000), Outbreak Period (1974-1987, the average annual incidence was 15.16/100 000), Low-level Epidemic Period（1988-2003, the average annual incidence was 1.68/100 000） and Epidemic Rebound Period (2004-2011, the average annual incidence was 4.82/100 000）. The incidence of scarlet fever in Guangdong appeared two seasonal peaks: the first peak (autumn peak) increased since September and reached the summit between November to January (the constituent ratio is 35.4%); the second peak (spring peak) is lower than the first peak which increased since March and reached the summit between April to June (the constituent ratio is 28.9%). The two peaks were almost in accordance with the school fall semester and spring semester, respectively. A total of 3 large outbreaks were reported in key areas of Guangdong. The first outbreak occurred in Shantou City in 1974 when 1 712 cases were reported (the incidence was 484.02/100 000) and children under 15 years of age accounted for 90.5% of all cases. Ten years later, the second outbreak occurred in the same city in 1984 when 360 cases were reported (the incidence was 80.62/100 000) and children under 15 years of age accounted for 91.4% of all cases. The third outbreak occurred in Zapo Town of Yangjiang County in 1987 when 690 cases were reported，children between 5 to 9 years old accounted for 14.6% of all cases.The incidence of scarlet fever in Guangdong rebounded in 2004-2011 and the top four cities for 2011 were Shenzhen (758 cases), Guangzhou (265 cases), Foshan (117 cases) and Dongguan (109 cases). The reported cases of these four cities in 2011 were higher than the average annual cases in 2004-2010 respectively and the biggest surge was in Shenzhen (increased by 422.7%). Compared with 2004-2010, the constituent ratio for preschoolers increased in 2011, but that for students declined (P<0.01). Conclusion The fluctuation pattern of the epidemic for scarlet fever in Guangdong Province during 1950 to 2011 is that high incidence period alternated with low incidence one. Each period lasted about 15 to 20 years. The epidemic rebounded since 2004 and increased obviously especially in 2011 which showed that it would remain the epidemic period for the next several years in the province. Childcare facilities and schools should be the focus of prevention and control for scarlet fever in the future.

Objective To understand the epidemiological characteristics of HIV/AIDS in Guangxi from 2009 to 2011, and to provide the scientific evidence for developing prevention and control strategies. Methods The accumulative data of reported HIV/AIDS cases by the end of 2009, 2010, and 2011, were downloaded from HIV/AIDS comprehensive prevention and control information system database. Statistical analysis of the epidemic information of the data was performed. Results A total of 36 669 HIV/AIDS cases were reported in Guangxi from 2009 to 2011, including 23 893 HIV infection cases (65.2%) and 12 776 AIDS cases (34.8%). Of them, 24 599 cases were male and 12 070, female. 24 095 cases were peasants (65.7%). The cases at 20-39 age group [JP2]accounted for the largest proportion, but was decreasing year by year, from 57.7% (43 660/75 716) in 2009 down to 36.1% (5 150/14 250) in 2011; cases at 60 years and above increased obviously to 28.4% (4 052/14 250）in 2011 from 18.7% (2 012/10 771）[JP]in 2009; the married accounted for 64.5%（23 664/36 669）, of whom, 52.4% （12 406/23 664）received partner testing with a testing positive rate of 56.0%（6 946/12 406）. Heterosexual transmission was the main transmission mode, accounting for 90.0%（12 821/14 250） of all in 2011. Most of men and women under the age of 40 years old had extramarital heterosexual contact history, and the proportion was 74.6% (18 998/25 466) and 60.5% (3 737/6 179) respectively; women over 40 years old were mainly infected by their HIV positive spouse, with the proportion of 52.4%（2 633/5 023）. From 2009 to 2011, 9 282 AIDS patients were died, including 4 471 death reported in the same year, accounting for 12.2% （4 471/36 669）of new reported cases, and 48.2% （4 471/9 282）of the deaths report in that year. Conclusion New reported HIV/AIDS cases and died cases showed a rising trend in Guangxi from 2009 to 2011, the place distribution of HIV cases was various in counties; heterosexual sex transmission route was the main one; the proportion of infected cases in the middle and older age group increased sharply; the problem of finding patients late is more serious. We should strengthen the surveillance of high-risk and key groups, find and treat the cases early, and conduct effective intervention into different groups to reduce new infections and mortality.

Objective To investigate the current condition of adaptation behaviors to heat wave, and further explore the related factors of adaptation behavior in residents of Guangdong Province. Methods A total of 2 183 adults were selected by a four-stage sampling method in Guangdong Province. A household member aged 15-69 years was determined using KISH table in each household to complete the questionnaire. Each subject was interviewed at his/her home with a structured questionnaire by a well trained investigator from September to November 2010. The questionnaire contained socio-demographic characteristics, heat wave related knowledge, awareness of heat wave, adaptation behaviors to heat wave, and personal world view. ANCOVA tests were employed in the present study. Results The average age of total 2 183 participants was 39.31±14.16 years, among which 1 164 (53.37%) were males, and 1 064 (48.74%) were selected from the urban. 38.62% of the participants reported that they knew about heat wave. The mean score of the risk perception in related to heat wave among the residents was 4.22(1-7). 98.05% of the participants employed at least one adaptation behavior during the heat wave; the most common adaptation behavior adopted was drinking more fluids (87.04%), the least adaptive behavior adopted was seeking an air-conditioned location (30.40%). The average adaptation score was 4.80±2.39. The scores were higher in middle-aged persons (P<0.05), participants with higher education (P<0.01), technicians and service personnel (P<0.01), and egalitarian (P<0.01). In addition, adaptation score was positively related to heat wave related knowledge (P<0.01), and heat wave related knowledge had an interactive effect with world view on adaptation score (P<0.01). Conclusion The adaptation level to heat wave was at moderate level in the residents of Guangdong Province, and the relative factors of adaptation included age, education, occupation, world view, and heat wave related knowledge. Moreover, the relationships between the heat wave related knowledge and adaptation could be moderated by world view.

Objective Through exploring the use of the moving average method and gray residual GM model to establish prediction early warning model and predict the epidemic tendency of bacillary dysentery in Guangdong Province, to provide scientific database for future prevention and control. Methods Bacillary dysentery incidence data in 2004-2011 in Guangdong Province were collected. We established Gray residual GM Model based on the moving average method (Type III) and adopted the average relative error, posterior difference, and small error probability as the test indicators to compare and analyze the traditional gray GM model (Type I) and Gray GM model based on the moving average method (Type II ). Results The results showed that: C=0.22, P =1.00, the accuracy of the model(Type III) is 1 (good), the average relative error is 5.21%. The model level and average relative error of Model (Type III) is relatively small compared with the other two models (types I and II). The estimates of incidence of bacillary dysentery in Guangdong Province in 2012, 2013, and 2014 using model (Type III) are 5.069 3/100 000, 4.514 0/100 000 and 4.027 0/100 000, respectively. Conclusion Gray residual GM model based on the moving average method (Type III) has the highest fitting accuracy compared with the other two models. It provides the evidence of feasibility and effectiveness to predict the epidemic tendency of bacillary dysentery in Guangdong Province.

Objective To investigate the HIV/AIDS-related knowledge, behavior, and influence factors in different people in Dongguan City to provide scientific basis for target interventions. Methods Worker, student and villager were selected to investigate the demographic information and AIDS-related knowledge in Dongguan City by clustering and convenient sampling methods. Results A total of 2 880 people including 1 385 males and 1 495 females were surveyed. The means of age of workers, students, and villager were 27.51 ± 6.70 years old, 16.16 ± 0.97 years old, and 35.46 ± 10.54 years old, respectively. For the educational level, 35.42% were junior middle school, 42.19% were senior middle school. The overall HIV/AIDS awareness rate was 91.77％（2 643/2 880）. The awareness rates on HIV/AIDS among workers, students, and villagers were 94.92%（915/964）, 91.88%（883/961）, and 88.48%（845/955）, respectively. Logistic regression analysis showed that the individuals living in the coastal area（OR=0.50）, aged in the 30-39 years old（OR=0.61）, married（OR=0.39）, with college education（OR=0.21） had higher HIV/AIDS knowledge, and those living in the area of hill or rivers and lakes （OR=1.95, 2.33）, students / villagers（OR=1.65, 2.43）, aged 40 years old and above（OR=1.31） had lower HIV/AIDS knowledge. Conclusion HIV/AIDS knowledge awareness rate seemed to be high and the effect is evident in the health education of HIV/AIDS knowledge. Propaganda and education should be strengthened to those people living in the area of rivers and lakes or hill, young age, with low education level, unmarried cohabitant, and the aged people to improve their HIV/AIDS knowledge awareness.