Age-specific prevalence of IgG against measles/rubella and the impact of routine and supplementary immunization activities: A multistage random cluster sampling study with mathematical modelling

• 出版年: International Journal of Infectious Diseases
• 主要な著者: Masahiko Hachiya, Emilia Vynnycky, Yoshio Mori, Hung Thai Do, Mai Kim Huynh, Long Hoang Trinh, Duy Duc Nguyen, Nhu Anh Thi Tran, Thanh Tien Hoang, Hai Hang Thi Hoang, Ngoc Dieu Thi Vo, Thieu Hoang Le, Yasunori Ichimura, Shinsuke Miyano, Sumiyo Okawa, Moe Moe Thandar, Yuta Yokobori, Yosuke Inoue, Tetsuya Mizoue, Makoto Takeda, Kenichi Komada
• フォーマット: 論文
• 言語: 英語
• 出版事項: Elsevier 2024-07-01
• 主題: Serosurvey; IgG prevalence; Mathematical modelling; Measles-rubella combined vaccine; Representative population
• オンライン･アクセス: http://www.sciencedirect.com/science/article/pii/S1201971224001231

Background: Vietnam continues to have measles and rubella outbreaks following supplementary immunization activities (SIA) and routine immunization despite both having high reported coverage. To evaluate immunization activities, age-specific immunity against measles and rubella, and the number of averted Congenital Rubella Syndrome (CRS) cases, must be estimated. Methods: Dried blood spots were collected from 2091 randomly selected individuals aged 1-39 years. Measles and rubella virus-specific immunoglobulin G (IgG) were measured by enzyme immunoassay. Results were considered positive at ≥120 mIU/mL for measles and ≥10 IU/mL for rubella. The number of CRS cases averted by immunization since 2014 were estimated using mathematical modelling. Results: Overall IgG seroprevalence was 99.7% (95%CI: 99.2-99.9) for measles and 83.6% (95%CI: 79.3-87.1) for rubella. Rubella IgG seroprevalence was higher among age groups targeted in the SIA than in non-targeted young adults (95.4% [95%CI: 92.9-97.0] vs 72.4% [95%CI: 63.1-80.1]; P < 0.001). The estimated number of CRS cases averted in 2019 by immunization activities since 2014 ranged from 126 (95%CI: 0-460) to 883 (95%CI: 0-2271) depending on the assumed postvaccination reduction in the force of infection. Conclusions: The results suggest the SIA was effective, while young adults born before 1998 who remain unprotected for rubella require further vaccination.