Trend of diseases among Iranian pilgrims during five consecutive years based on a Syndromic Surveillance System in Hajj

Background: Every year more than 2 million people depart from Iran to Saudi Arabia for Hajj ritual which can be faced with some different diseases. There are not much information about frequencies and trend of dis-eases in Hajj. The main objective of this study was to determine the trend of prevalent diseases during five con-secutive Hajj rituals among Iranian pilgrims. Methods: We established a specific surveillance system for all Iranian pilgrims who had participated in Hajj from 2004 to 2008. We monitored the pilgrims’ health status before departure, through their journey. The un-derstudied diseases were 19 selected types of diseases in the Hajj. The occurrences of diseases were recorded on a researchers-made questionnaire. We used chi-square test for analysis with the alpha lower than 5% to reject the null hypothesis. Results: During 5 consecutive periods, a total of 254,823 of Iranian pilgrims were monitored for more com-mon diseases with this system. The most prevalent diseases were as follows: at least one type of respiratory involvement (71.26%), common cold like syndrome (47.15%), and musculoskeletal disorders (18.67%), The frequency of respiratory involvement was lower in 2006 than other years (p < 0.001).There were statistically significant differences between the numbers of hospitalization and patients who were referred back to Iran with the year of Hajj (p < 0.001). Conclusion: Health managers should be informed about trend and frequency of more prevalent diseases in Hajj. Easy access to health information via such surveillance system can be possible.