Background: Mobile-based social media play an important role in the dissemination of information during public health emergencies. Objectives: This study aimed to analyze the contents and trends of public messages posted on Telegram during Coronavirus Disease 2019 (COVID-19) pandemic. Methods: A content analysis of the 1781 messages, posted in a public Telegram channel with more than one million subscribers performed over 9-weeks. The messages were categorized into seven categories. Results: In total, 39% (n=703) of all messages were related to COVID-19. With the official confirmation of the case of COVID-19 in Iran, the number of COVID-related massages started to rise. Overall, the most frequent messages were of joke and humor (n=292, 41.5%), followed by educational messages (n=140, 19.9%). Conclusion: Our study showed that the most popular messages during first weeks of COVID pandemic were satirical, indicating that people may not had taken the risks of this pandemic seriously. It is crucial for health organizations to develop strategies for dissemination of reliable health information through social media.

Condom use has been known as the most effective method of preventing sexually transmitted diseases. The purpose of the present study was to find the factors affecting the use of condoms by female sex workers in Iran. This cross-sectional study was conducted on 872 female sex workers in Iran in 2010. The criterion of admission to the study included having sexual relationships over the last week based on which 437 women were selected. The weighted negative binomial hurdle model, and Stata14 were used to analyze the data. Generally, 34.93% of the female sex workers did not use condoms over the last 7 days. According to the results, the increase in the education level and not being single increased the odds and the rate number of using condoms concerning the number of sexual relationships of the sex workers. Besides, the increase in age and having a non-paying sexual partner in return for the sexual relationship decreased the odds of using condoms by female sex workers. Finally, the female sex workers who were tested for HIV and the ones knowing the centers distributing free condoms were more likely to use the condom. The illiterate and married female sex workers are considered as the high-risk groups in the community. Therefore, it is of great importance to plan to form the educational interventions connected with the high-risk sexual relationships.