[Introduction of pertussis surveillance system and evaluation of its operational effect in Tianjin].

The pertussis surveillance system has been established since 2009 in Tianjin, and continuously improved over the past 10 years. This system determines the definition and classification of pertussis, establishes simple and feasible sampling methods and laboratory detection methods in clinical practice, standardizes the report management of pertussis cases and the treatment of epidemic situations. After the implementation of the surveillance system, the number of reported pertussis cases increased from 26 in 2009 to 802 in 2017, the number of diagnosed cases increased from 19 in 2009 to 662 in 2017, the reported incidence rate of pertussis increased from 0.

[Influences of genetic and environmental factors on smoking related behaviors among male twin adults in China].

Objective: To analyze the influences of genetic and environmental factors on smoking behavior, smoking cessation and onset age of smoking less than 20 years in male twin adults.

Methods: A face-to-face questionnaire was conducted to collect data from 6 458 pair male twins aged ≥25 years registered in 9 provinces(municipality)in China. The heritability of three smoking related behaviors were calculated by using structural equation models.