Acquisition of respiratory and gastrointestinal pathogens among health care workers during the 2015 Hajj season

International audienceBackground: Data on the risk of transmission of infection to health care workers (HCWs) serving ill pilgrims during the Hajj is scarce.Methods: Two cohorts of HCWs, the first serving Hajj pilgrims in Mecca and the second serving patients in Al-Ahsa, were investigated for respiratory and gastrointestinal symptoms and pathogen carriage using multi-plex polymerase chain reaction before and after the 2015 Hajj.Results: A total of 211 HCWs were enrolled of whom 92 were exposed to pilgrims (Mecca cohort), whereas 119 were not exposed (Al-Ahsa cohort). Symptoms were observed only in HCWs from the Mecca cohort, with 29.3% experiencing respiratory symptoms during the Hajj period or in the subsequent days and 3.3% having gastrointestinal symptoms. Acquisition rates of at least 1 respiratory virus were 14.7% in the Mecca cohort and 3.4% in the Al-Ahsa cohort (P = .003). Acquisition rates of at least 1 respiratory bacterium were 11.8% and 18.6% in the Mecca and Al-Ahsa cohorts, respectively (P = .09). Gastrointestinal pathogens were rarely isolated in both cohorts of HCWs and acquisition of pathogens after the Hajj was documented in only a few individuals.Conclusions: HCWs providing care for pilgrims both acquire pathogens and present symptoms (especially respiratory symptoms) more frequently than those not working during Hajj