Epidemiological characteristics of invasive meningococcal disease and carriage prevalence of in the Xinjiang Uygur Autonomous Region, China, 2004-2023: a retrospective study.

Objective: The Xinjiang Uygur Autonomous Region (Xinjiang) currently exhibits the high incidence rates of invasive meningococcal disease (IMD) in China. Current epidemiological data on meningococcal carriage rates among asymptomatic individuals remain sparse, with limited population-based studies systematically investigating the prevalence of colonization in the general population. This study employs a dual-pronged epidemiological approach to systematically characterize the clinical-epidemiological profile of IMD in Xinjiang and quantify the nasopharyngeal carriage prevalence of among asymptomatic populations, while identifying region-specific sociodemographic and behavioral determinants of carriage dynamics.

Methods: Epidemiological characteristics were analyzed using descriptive epidemiological methods. strains isolated from asymptomatic carriers underwent serogroup characterization multiplex real-time polymerase chain reaction (real-time PCR) targeting conserved capsular biosynthesis loci (serogroups A, B, C, W, X, and Y), with reaction conditions optimized per WHO standardized protocols for meningococcal molecular typing. The test was used to compare the carriage rates. A multivariable logistic regression model was used to analyze the risk factors associated with the carriage of .

Results: From 2004 to 2023, 1,100 cases of IMD were reported in Xinjiang, with the annual incidence rate fluctuating between 0.00/100,000 and 1.15/100,000 per year. The peak incidence occurred from February to May. The incidence was primarily concentrated in individuals under 20 years old (80.36%). Among 3,075 oropharyngeal swab specimens analyzed, 411 (13.37%; 95% CI [12.18-14.62]) yielded culture-confirmed isolates. Serogroup B (168, 40.88%) emerged as the predominant meningococcal serogroup. Binomial multivariate logistic regression analyses indicated significant associations between the carriage rate of and age, sex, year, region, and vaccination history ( < 0.05).

Conclusion: Epidemiological surveillance data from 2004 to 2023 revealed a significant decline in the incidence of IMD across Xinjiang, with the epidemiological profile transitioning from cyclic epidemic peaks to sporadic case clusters. Despite this decline, the carriage rate of remained at elevated levels among healthy populations. The risk of carrying was relatively high among the healthy population in the southern region of Xinjiang, people aged over 16, and those without a vaccination history. Strengthening IMD surveillance in high-risk areas is essential to prevent future outbreaks.