Abstract
Background: Results showing that sera from double vaccinated individuals have minimal neutralizing activity against Omicron have been interpreted as indicating the need for a third vaccine dose for protection. However, there is little information about early immune responses to Omicron infection in double vaccinated individuals.
Methods: We measured inflammatory mediators, antibodies to the SARS-CoV-2 spike and nucleocapsid proteins, and spike peptide-induced release of interferon gamma in whole blood in 51 double-vaccinated individuals infected with Omicron, in 14 infected with Delta, and in 18 healthy controls. The median time points for the first and second samples were 7 and 14 days after symptom onset, respectively.
Findings: Infection with Omicron or Delta led to a rapid and similar increase in antibodies to the receptor-binding domain (RBD) of Omicron protein and spike peptide-induced interferon gamma in whole blood. Both the Omicron- and the Delta-infected patients had a mild and transient increase in inflammatory parameters.
Interpretation: The results suggest that two vaccine doses are sufficient to mount a rapid and potent immune response upon infection in healthy individuals of with the Omicron variant.
Funding: The study was funded by the Oslo University Hospital, and by grants from The Coalition for Epidemic Preparedness Innovations, Research Council of Norway (no 312780, 324272), South-Eastern Norway Regional Health Authority (no 2019067, 2021071, 10357, 2021047, 33612, 2021087, 2017092), EU Horizon 2020 grant no 848099, a philantropic donation from Vivaldi Invest A/S, and The European Virus Archive Global.
Keywords: Breakthrough infection; SARS-CoV-2; antibody; cellular immunity; human; vaccine.
【저자키워드】 SARS-CoV-2, Vaccine, antibody, Human, cellular immunity, Breakthrough infection, 【초록키워드】 Vaccine, immune response, variant, Infection, Delta, omicron, vaccine dose, Protein, Neutralizing activity, Whole blood, RBD, sera, Patient, Mild, information, university, Norway, interferon gamma, cellular, Inflammatory mediators, inflammatory parameters, symptom onset, median time, individual, Nucleocapsid proteins, healthy controls, Horizon, vaccinated individuals, Coalition, vaccinated individual, archive, authority, Council, Regional, European, Result, the receptor-binding domain, increase in, in healthy individual, early immune response, the SARS-CoV-2, 【제목키워드】 Infection, delta variant, Vaccine-induced immunity,