Iranian Journal of

---

  Background & Objectives : Health risk behaviors in adolescence, such as alcohol consumption and smoking, can affect both short-term and long-term health. The aim of study was to estimate the prevalence of health risk behaviors among high school students of Qazvin.

  Methods : The target population of this descriptive study was all high school students of Qazvin who were enrolled in the 1390-91 academic year. The sample group included 160) 239 girls, 271 boys) students that were selected by randomly multistage sampling. The assessment instrument was the Youth Risk Behaviors Surveillance System (YRBSS) Questionnaire.

  Results: Findings indicated that use of hookah was the most popular in girls and boys (59%) as compared with cigarette smoking (32.7%), drug use (7.3%), and alcohol consumption (16.7%). The prevalence of physical violence in and outside the school in one year, carrying weapons to school in a month, cigarette smoking in the school in one month, smoking hookah, and alcohol and opioid use during one month were more frequently observed in boys than girls. The use of the seat belt was more common among girls than boys, and the total prevalence of using the seat belt was 23.7%.

  Conclusion : Given the high prevalence of high risk behaviors among high school students, it is necessary to develop a high risk behaviors surveillance system and use the obtained information to devise preventive measures at the individual, school, and family levels.

---

 
Background and Objectives: Avian influenza (AI) is one of the most important respiratory diseases in the poultry industry that causes huge economic impacts and plays an important role in public health. H9N2 Avian Influenza Virus (H9N2 AIV) has a broad circulation and causes endemic infections in the poultry industry of the country.
 
Methods: A cohort study was conducted from July 2016 to November 2017 in broiler chicken farms of Qazvin Province, Iran to detect H9N2 AIV infection determinants in broiler chicken farms.
 
Results: Sixteen out of 34 units that were included in the study had positive PCR results. Some variables such as “type of fence around the unit”, “biosecurity”, “cooling system status”, “mean maternal antibody titers”, “location height”, “proximity to public traffic lanes” and “number of units within a radius of 1 km” had significant effects on the infection occurrence in poultry units according to univariate statistical analyses (P<0.05). However, only two of them (“biosecurity” and “cooling system status”) were statistically significant in multi-variable analyses (P<0.05).
 
Conclusion: Biosecurity measures should be implemented more seriously and strictly in broiler farms to reduce the impact of H9N2 AIV infection.