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Background: Intense congestion during the Hajj pilgrimage amplifies the risk of meningococcal carriage and disease, and there have been many meningococcal outbreaks reported amongst pilgrims. Thus, a strict vaccination policy is enforced by the host country and either polysaccharide or conjugate quadrivalent meningococcal vaccines are mandatory. However, unlike conjugate vaccines, the polysaccharide vaccine is not thought to reduce pharyngeal carriage of meningococci., Methods: A single-blinded, randomized, controlled trial amongst pilgrims from Saudi Arabia and Australia during the Hajj seasons of 2016-2017 was conducted to compare MenACWY-Conjugate vaccine with MenACWY-Polysaccharide vaccine, to determine if the conjugate vaccine is more effective in reducing asymptomatic carriage of meningococci, and whether the effect may be long-standing. Oropharyngeal swabs were obtained pre-, immediately post- and 6-11 months following completion of Hajj and tested for the presence of meningococci., Results: Amongst 2000 individuals approached, only 1146 participants aged 18-91 (mean 37.6) years agreed to participate and were randomized to receive either the polysaccharide (n = 561) or the conjugate (n = 561) vaccine, 60.8% were male, and 93.5% were from Saudi Arabia. Amongst oropharyngeal swabs obtained before Hajj, only two (0.2%) tested positive for Neisseria meningitidis. Similarly, meningococci were identified in only one sample at each of the post-Hajj and late follow-up visits. None of the carriage isolates were amongst the serogroups covered by the vaccines. A post hoc analysis of the third swabs revealed that 22.4% of all participants (50/223) were positive for Streptococcus pneumoniae nucleic acid., Conclusion: The low overall carriage rate of meningococci found amongst Hajj pilgrims in 2016 and 2017 demonstrates a successful vaccination policy, but neither supports nor refutes the superiority of meningococcal conjugate ACWY vaccine over the polysaccharide vaccine against carriage. Although an association could not be established in this study, molecular epidemiology would help to establish the role of Hajj in facilitating transmission of pneumococci and inform vaccination policy., (© International Society of Travel Medicine 2020. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background : Influenza is a common respiratory infection at Hajj. Thus, influenza vaccine is recommended for Hajj pilgrims but data on its effectiveness from a large sample are unavailable. This analysis aims to assess the effectiveness of the trivalent seasonal influenza vaccine (TIV) among Hajj pilgrims. Patients and methods : A 'test-negative' case-control analysis using data from individual studies was conducted. Included studies involved participants from Saudi Arabia, India, Australia and the United Kingdom who attended Hajj in Makkah, Saudi Arabia in different years between 2005 and 2015. Pilgrims who developed symptoms of respiratory infection during Hajj were included in these studies. Participants' vaccination histories were recorded and respiratory samples were collected to test for influenza by PCR. Vaccine effectiveness (VE) was calculated after adjusting for potential confounders. Results : A total of 1,569 pilgrims were included in this analysis. Influenza vaccine uptake was 52.2% and the attack rate of influenza was 8.2%. The estimated overall VE was 43.4% (95% CI 11.4% to 63.9%, P = 0.01). VE against a specific subtype of influenza was not significant. Conclusion : The current analysis has shown that TIV is moderately effective among Hajj pilgrims, but the vaccine uptake has been suboptimal. Power was much reduced when testing for influenza subtypes.