Background
Pilgrimages and travel to religious mass gatherings (MGs) are part of all major religions. This narrative review aims to describe some characteristics, including health risks, of the more well-known and frequently undertaken ones.
Methods
A literature search was conducted using keywords related to the characteristics (frequency of occurrence, duration, calendar period, reasons behind their undertaking and the common health risks) of Christian, Muslim, Hindu, Buddhist and Jewish religious MGs.
Results
About 600 million trips are undertaken to religious sites annually. The characteristics vary between religions and between pilgrimages. However, religious MGs share common health risks, but these are reported in a heterogenous manner. European Christian pilgrimages reported both communicable diseases, such as norovirus outbreaks linked to the Marian Shrine of Lourdes in France, and non-communicable diseases (NCDs). NCDs predominated at the Catholic pilgrimage to the Basilica of Our Lady of Guadalupe in Mexico, which documented 11 million attendees in 1 week. The Zion Christian Church Easter gathering in South Africa, attended by ~10 million pilgrims, reported mostly motor vehicle accidents. Muslim pilgrimages such as the Arbaeen (20 million pilgrims) and Hajj documented a high incidence of respiratory tract infections, up to 80% during Hajj. Heat injuries and stampedes have been associated with Hajj. The Hindu Kumbh Mela pilgrimage, which attracted 100 million pilgrims in 2013, documented respiratory conditions in 70% of consultations. A deadly stampede occurred at the 2021 Jewish Lag BaOmer MG.
Conclusion
Communicable and NCD differ among the different religious MGs. Gaps exists in the surveillance, reporting and data accessibility of health risks associated with religious MGs. A need exists for the uniform implementation of a system of real-time monitoring of diseases and morbidity patterns, utilizing standardized modern information-sharing platforms. The health needs of pilgrims can then be prioritized by developing specific and appropriate guidelines.