Description: Publication date: 25 July 2018 Source: Vaccine, Volume 36, Issue 31 Author(s): Saber Yezli, Philippe Gautret, Abdullah M. Assiri, Bradford D. Gessner, Badriah Alotaibi Meningococcal disease is a serious public health threat given the seriousness of the illness, its disabling sequelae and its potential for epidemic spread. The disease is a concern during mass gatherings which provide conditions that facilitate transmission of infectious agents including Neisseria meningitidis . Implementation of appropriate meningococcal disease preventive measures during at-risk mass gatherings is crucial to prevent illness and outbreaks which may result in significant morbidity and mortality as well as local and international spread of the disease. These preventive measures should be informed by comprehensive risk assessments of the disease at those events and may include the use of vaccination, chemoprophylaxis and health awareness and educational campaigns, supported by efficient disease surveillance and response systems. The Hajj and Umrah religious mass gatherings in the Kingdom of Saudi Arabia are examples of how the implementation of such preventive measures was successful in reducing the incidence of meningococcal disease during these events as well as controlling and preventing outbreaks. Lessons learned from the Hajj and Umrah experience can inform meningococcal disease preventive strategies for other mass gatherings worldwide.