The impact of meningococcal conjugate vaccine (MenACWY-TT) on meningococcal carriage in Hajj Pilgrims returning to Turkey

Meningococcal conjugate vaccine was administered for the first time to pilgrims in 2018 in Turkey prior to their departure to the Hajj. This study aimed to determine the effect of vaccination on the prevalence of Neisseria meningitidis carriage among the pilgrims returning to Turkey. This prospective paired (departing and arriving) cohort study included pilgrims aged 10-80 years and compared N.meningitidis carriage before and after pilgrimage. Oropharyngeal samples were collected from 229 pilgrims before departing for Mecca, Kingdom of Saudi Arabia (KSA) and after their return to Turkey. Meningococcal carriage was detected in 3.9% (n = 9) at the time of departure; all positive samples were serogroup B. Upon returning to Turkey,1 (0.4%) pilgrim, who was not a carrier before pilgrimage, was positive for serogroup B. This study is the first to examine meningococcal carriage following the administration of conjugate vaccine to Hajj pilgrims from Turkey.