Syndromic surveillance of respiratory-tract infections and hand hygiene practice among pilgrims attended Hajj in 2021: A cohort study

Abstract Background: This cohort study estimated the incidence of symptomatic respiratory tract infections (RTIs) and hand hygiene compliance with its impact among domestic Hajj pilgrims during the COVID-19 pandemic. Methods: During the week of Hajj rituals in 2021, pilgrims were recruited by phone and asked to complete a baseline questionnaire. Pilgrims were followed up after seven days using a questionnaire about the development of symptoms, and practices of hand hygiene. Syndromic definitions were used to clinically diagnose ‘possible’ influenza-like illnesses (ILI) and COVID-19 infection. Results: A total of 510 pilgrims aged between 18 and 69 (median of 50) years completed the questionnaire, 280 (54.9%) of whom were female, and all of them (except for one) were vaccinated against COVID-19 with at least one dose. The mean (±SD) of pilgrims’ hand hygiene knowledge score (on a scale of 0 to 6) was 4.15 (±1.22), and a higher level of knowledge was correlated with a higher frequency of handwashing using soap and water. Among those 445 pilgrims who completed the follow-up form, 21 (4.7%) developed one or more respiratory symptoms, of which sore throat and cough were the commonest (respectively 76.2% and 42.8%); ‘possible ILI’ and ‘possible COVID-19’ were present in 1.1% and 0.9% of pilgrims. Obesity was found to be a significant factor associated with the risk of developing RTIs (odds ratio = 4.45, 95% confidence interval 1.15–17.13).Conclusion: Hajj pilgrims are still at risk of respiratory infections. Further larger and controlled investigations are needed to assess the efficacy of hand hygiene during Hajj.