Meningococcal Vaccine Among Domestic Hajj Pilgrims: A Large-Scale Assessment of Coverage, Facilitators, and Barriers.

BACKGROUND: Invasive meningococcal disease (IMD) remains a critical threat during Hajj. Following a 2024 resurgence of travel-related IMD cases, assessing domestic adherence to mandatory quadrivalent (MenACWY) meningococcal vaccination has become a public health priority. While international compliance is high, data on domestic pilgrims who constitute 25-40% of the population remain limited. AIM: To assess Meningococcal vaccine coverage and identify the sociodemographic determinants, motivators, and barriers among domestic pilgrims. METHODS: We analyzed data from a large-scale cross-sectional assessment of 4,678 domestic pilgrims (aged ≥16 years) conducted in Mina during the 2019 Hajj. As the final full-scale pilgrimage prior to the coronavirus disease 2019 pandemic, this cohort provides the definitive baseline for understanding domestic vaccination realities. Using multi-stage cluster sampling, participants were surveyed on several domains; this study specifically analyzed MenACWY uptake (within the required validity period), sociodemographics, and motivators. RESULTS: Overall uptake was 87.3%, but policy-compliant adherence was 86.2%. Multivariate analysis showed nonadherence was significantly associated with residency in Makkah Province (adjusted odds ratio [aOR] = 0.51, 95% confidence interval [CI]: 0.35-0.75, P < 0.001) and prior Hajj experience (aOR = 0.48, 95% CI: 0.33-0.70, P = <0.001). Conversely, female sex (aOR = 1.86, 95% CI: 1.01-3.42, P = 0.045), healthcare employment (aOR = 2.13, 95% CI: 1.20-3.75, P = 0.009), and the receipt of pre-Hajj health advice (aOR = 2.60, 95% CI: 1.79-3.77, P < 0.001) were linked with increased adherence. While policy mandate was the primary motivator (47.6%), 6.2% reported out-of-pocket costs, with non-citizens 4.14 times more likely to incur expenses ( P < 0.001). CONCLUSION: Domestic pilgrims exhibit suboptimal adherence, suggesting that geographic proximity and prior pilgrimage experience foster a familiarity-driven complacency that diminishes perceived risk. These findings from the 2019 baseline are vital for tailoring current strategies. Linking permit issuance to timely vaccination is essential to achieve the coverage required for Hajj health security.