Survey of HIV infection in men who have sex with men living for 5 years or less in Wenzhou, Zhejiang province / 中华流行病学杂志

Objective: To assess the prevalence of HIV infection and related factors in men who have sex with men (MSM) living for ≤5 years in Wenzhou of Zhejiang province. Methods: MSM who were aged ≥16 years, had lived in Wenzhou for ≥3 months and had anal sex and/or oral sex with men in the last 12 months were recruited through respondent-driven sampling (RDS) from February to October in 2015. The MSM recruited completed a questionnaire for the information collection on socio-demographic characteristics, sexual behavior, awareness of HIV and related intervention, mental health status. Blood samples were collected from them for serological detection of HIV and syphilis antibodies. Software SPSS 18.0 was used to analyze HIV infection and related factors. Results: A total of 454 MSM were investigated, 108 of them (23.7%) were HIV positive. There were 267 MSM who lived in Wenzhou for ≤5 years, and 73 of them (27.3%) were HIV positive. Most of them were workers and commercial servants aged ≥25 years with personal monthly income <4 000 yuan and educational level of junior high school or below. According to multiple logistics regression analysis, age of 25-68 years old (OR=12.19, 95%CI: 2.29-65.02), heterosexual behavior in recent 6 months (OR=0.42, 95%CI: 0.18-0.96), believing it was possible to be infected with HIV (OR=0.06, 95%CI: 0.01-0.95), believing it was impossible to be infected with HIV (OR=0.03, 95%CI: 0.01-0.35) and syphilis status (OR=3.32, 95%CI: 1.05-10.52) were the risk factors associated with HIV infection. Conclusion: Compared with MSM who lived in Wenzhou for >5 years, MSM who lived in Wenzhou for ≤5 years had higher HIV infection rate and higher prevalence of risk behavior. It is necessary to conduct targeted intervention among them.

Establishment of the classified evaluation system on the levels of influenza epidemics through a synthetic index method, in Beijing / 中华流行病学杂志

Objective: To establish a classified evaluation system for recognizing the levels of influenza epidemics and to explore the new reporting system on influenza epidemics. Methods: The following 3 indicators, including 1) the number of influenza-like illness, 2) positive rate of detection on influenza virus nucleic acids, and 3) the number of influenza outbreaks were chosen to calculate the synthetic index and to classify the grades of evaluation. Results: 209 weeks during 2013-2017 were classified into 5 grades: Grade 1 were 110 weeks (52.63%), Grade 2 were 47 weeks (22.49%), Grade 3 were 44 weeks (21.05%), Grade 4 were 8 weeks (3.83%), and Grade 5 were 0 week. Conclusion: This classified evaluation system provided simple, comprehensive and comparable reference indicators and used for the evaluation on influenza epidemics, also providing suggestions for influenza prevention and control accordingly.

Environmental biological model based on optimization of activated sludge process

A simplified environmental biological model has been developed based on biodegradation kinetics correlation to regulate and optimize wastewater treatment system of activated sludge process. All parameters included in the model are calibrated in accordance with reference data and experimental results and good agreements are achieved between calculated results and reference data or experimental results. The minimum bioreactor volume is used as objective function in the model and errors between optimal minimum volume of the model and each reported result of three references are found to be no more than 8.63% after validation. Comparisons between optimal results and experimental data demonstrate that the deviations are negligible. The optimal minimum volume is 9.21 m3 with the error of 6.40% to the practical bioreactor volume of a pilot treatment system. The environmental biological model has been applied to economically evaluate a former treatment system with native bacterium YZ1 and four operation periods of the pilot system with functional strain Fhhh compared with YZ1, Fhhh possesses higher biodegradation ability in purified terephthalic acid wastewater and a broader economic potential in the field of wastewater treatment