Analysis on the epidemic and genetic characteristics of varicella in Fengtai District, Beijing City, 2024-2025
10.3760/cma.j.cn112150-20250414-00307
- VernacularTitle:2024—2025年北京市丰台区水痘流行情况及基因特征分析
- Author:
Yudan ZHENG
1
;
Bei LAN
;
Wanqi HOU
;
Tao YAN
;
Aihua LI
;
Meng QIN
Author Information
1. 北京市丰台区疾病预防控制中心微生物检验科，北京100071
- Publication Type:Journal Article
- Keywords:
Varicella;
Breakthrough infection;
Genotype;
Epidemiological feature
- From:
Chinese Journal of Preventive Medicine
2025;59(7):1113-1117
- CountryChina
- Language:Chinese
-
Abstract:
This study analyzed the epidemiological characteristics and strain genotypic distribution of varicella in Fengtai District, Beijing, utilizing population-based surveillance data from March 2024 to February 2025 combined with laboratory nucleic acid detection and genotyping.We reported 522 varicella cases with male predominance (282 cases, 54.41%) and a majority aged >15 years (358 cases, 68.58%).A bimodal incidence pattern peaked in May and November, while 161 breakthrough infections (30.8%) occurred predominantly among students aged 6-20 years.The multivariate logistic regression model analysis showed that, compared to the 0-5 years age group, individuals aged 6-14 years ( OR: 2.729, 95% CI: 1.083-6.88), 15-20 years ( OR: 2.495, 95% CI: 1.158-5.378), and>20 years ( OR: 5.382, 95% CI: 2.478-11.689) exhibited progressively higher odds of oderate-to-severe rash; females demonstrated a lower risk compared to males ( OR: 0.485, 95% CI: 0.286-0.822); regarding vaccination status, recipients of one vaccine dose ( OR: 0.301, 95% CI: 0.161-0.564) and two doses ( OR: 0.203, 95% CI: 0.086-0.48) showed significantly reduced risks relative to unvaccinated individuals. Genotyping of 174 specimens identified 161 VZV-positive samples, with successful ORF22/38/62 sequencing in 142 samples confirming Clade 2 predominance (141 strains, 99.3%) and one Clade 5 strain; local isolates exhibited high vaccine-strain homology (ORF22 nucleotide:99.5%-100%, amino acid:99.3%-100%) with mutation sites partially overlapping other Chinese regions.
