Pediatric population (aged 3-11 years) received primary inactivated SARS-CoV-2 vaccination prior to infection exhibiting robust humoral immune response following infected with Omicron variant: a study conducted in Beijing

• DOI: 10.3389/fimmu.2023.1269665
• Publication Date: 2023-09-28T05:32:18Z
• Authors: Jing Li; Jingjing Li; Shuzhi Dai; Li Dang; Lin Wang; Ling Cao; Xiaobo Chen; Ying Wang; Menglei Ge; Weijie Liu; Qinwei Song; Wenjian Xu; Lijuan Ma
• Keywords: COVID-19 Vaccines; SARS-CoV-2; SARS-CoV-2 infection; Immunology; Vaccination; neutralizing antibody; COVID-19; RC581-607; vaccination; Antibodies, Viral; Antibodies, Neutralizing; 3. Good health; Immunity, Humoral; children; Beijing; Immunoglobulin G; Blood Group Antigens; Humans; Immunologic diseases. Allergy; Child

Analysis of SARS-CoV-2 IgG antibody and neutralizing levels following infection in children aged 3-11 years, comparing those who had received the inactivated vaccine to were unvaccinated prior infection, provides evidence for public health centers formulating vaccination strategies control policies.A study was conducted on visited Children's Hospital, Capital Institute Pediatrics from January 10, 2023 March 31, (Beijing, China). Participants or their guardians completed a survey questionnaire providing information about history status. Serum samples collected testing immunoglobulin G (IgG) antibodies (Nabs), which performed using chemiluminescence immunoassay.The included 1,504 years with previous history. Among 333 children, serum level median 2.30 (IQR, 1.27-3.99). However, one dose (78 cases) two doses (1093 showed significantly higher levels, values 10.11 8.66-10.93) 10.58 9.79-11.07), respectively. As 70.3% (234/333) negative Nabs, less than 6.00AU/ml. The remaining 29.7% (99/333) relatively low ranging 6.00 50.00AU/ml. In contrast, an overwhelming 99.3% (1086/1093) exhibited high Nas range 100.00-120.00 AU/ml. Remarkably, these elevated Nab persisted at least period 3 months post-infection regardless age sex manufacturer.The administration has been shown enhance humoral immunity pediatric populations, producing adequate Nabs that persist up post-infection. For displayed weak primary natural timely is recommended bolster immunization protection. findings underscore importance strengthening immune responses protecting populations against infection.