Publication date: Jul 11, 2023
In the situation of mass vaccination against COVID-19, few studies have reported on the early kinetics of specific antibodies (IgG/IgM/IgA) of vaccine breakthrough cases. There is still a lack of epidemiological evidence about the value of serological indicators in the auxiliary diagnosis of COVID-19 infection, especially when the nucleic acid results were undetectable. Omicron breakthrough cases post-inactivated vaccination (n = 456) and COVID-19-naive individuals with two doses of inactivated vaccination (n = 693) were enrolled. Blood samples were collected and tested for SARS-CoV-2 antibody levels based on the magnetic chemiluminescence enzyme immunoassay. Among Omicron breakthrough cases, the serum IgG antibody level was 36. 34 Sample/CutOff (S/CO) (95% confidence interval [CI], 31. 89 to 40. 79) in the acute phase and 88. 45 S/CO (95% CI, 82. 79 to 94. 12) in the recovery phase. Serum IgA can be detected in the first week post-symptom onset (PSO) and showed an almost linear increase within 5 weeks PSO. Compared with those of breakthrough cases, IgG and IgA titers of the postimmune group were much lower (4. 70 S/CO and 0. 46 S/CO, respectively). Multivariate regression showed that serum IgG and IgA levels in Omicron breakthrough cases were mainly affected by the weeks PSO (P
| Concepts | Keywords |
|---|---|
| 5weeks | early kinetics |
| Antibodies | Omicron breakthrough infection |
| Covid | SARS-CoV-2 |
| Inactivated | specific antibodies |
| Postimmune | vaccinated |
Semantics
| Type | Source | Name |
|---|---|---|
| disease | MESH | COVID-19 |
| disease | VO | vaccination |
| disease | VO | vaccine |
| disease | VO | LACK |
| disease | MESH | infection |
| disease | IDO | blood |
| disease | IDO | symptom |
| disease | MESH | breakthrough infection |
| disease | VO | vaccinated |