Objective: The influence of age, period, and cohort on Hepatitis B (HB) incidence in four prefectures of southern Xinjiang, China is still not clear. This paper aims to analyze the long-term trend of the HB incidence in four prefectures of southern Xinjiang, China and to estimate the independent impact of age, period and cohort, as well as to predict the development trend of HB incidence in male and female groups, then to identify the targeted population for HB screening by the model fitting and prediction. Method: The data were from the Case List of HB Cases Reported in the Infectious Disease Reporting Information Management System and the Xinjiang Statistical Yearbook of China. The age-period-cohort (APC) model was used to estimate the impacts of age, period and cohort on HB incidence, which could be used to predict the HB incidence in specific age groups of men and women. Results: Under the influence of age effect, the incidence of HB in males had two peaks (20–35 years old and 60–80 years old), the influence of age effect on the incidence of HB in females was lower than that of males and the obvious peak was between 20–30 years old; the period effect on the HB incidence in males and females fluctuated greatly and the fluctuation degree of influence on males was bigger than that of women. The HB incidence among males and females in the four regions tended to be affected by cohort effect, which reached a peak after 1990 and then declined sharply and gradually became stabilized. By predicting the HB incidence from 2018 to 2022, we found that there were significant differences in HB incidence among people over 35 years old, under 35 years old and the whole population in four prefectures of southern Xinjiang, China. Conclusions: Although the incidence of HB in some regions shows a downward trend, there is still an obvious upward trend of incidences in other places. In our paper, results indicate that the burden of HB incidence may be extended in the future, so we hope this can draw the attention of relative departments. These results reveal the differences of incidence between males and females as well, so respective measures of the two groups’ functions are essential.

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 Neisseria meningitidis 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 N. meningitidis among asymptomatic populations, while identifying region-specific sociodemographic and behavioral determinants of carriage dynamics. Methods: Epidemiological characteristics were analyzed using descriptive epidemiological methods. N. meningitidis strains isolated from asymptomatic carriers underwent serogroup characterization via 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 ${\chi^2}$ test was used to compare the N. meningitidis carriage rates. A multivariable logistic regression model was used to analyze the risk factors associated with the carriage of N. meningitidis. 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 N. meningitidis 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 N. meningitidis and age, sex, year, region, and vaccination history (p < 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 N. meningitidis remained at elevated levels among healthy populations. The risk of carrying N. meningitidis 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.