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Major Update 2: Antibody Response and Risk for Reinfection After SARS-CoV-2 Infection-Final Update of a Living, Rapid
Haley K Holmer1, Katherine Mackey2, Celia V Fiordalisi1
1Scientific Resource Center for the Agency for Healthcare Research and Quality, Portland, Oregon (H.K.H., C.V.F.).
Background:
The durability of the antibody response after SARS-CoV-2 infection and the role of antibodies in protection against reinfection are unclear.
Purpose:
To synthesize evidence on the SARS-CoV-2 antibody response and reinfection risk with a focus on gaps identified in our prior reports.
Data Sources:
MEDLINE (Ovid), EMBASE, CINAHL, World Health Organization Research Database, and reference lists from 16 December 2021 through 8 July 2022, with surveillance through 22 August 2022.
Study Selection:
English-language, cohort studies evaluating IgG antibody duration at least 12 months after SARS-CoV-2 infection, the antibody response among immunocompromised adults, predictors of nonseroconversion, and reinfection risk.
Data Extraction:
Two investigators sequentially extracted study data and rated quality.
Data Synthesis:
Most adults had IgG antibodies after SARS-CoV-2 infection at time points greater than 12 months (low strength of evidence [SoE]). Although most immunocompromised adults develop antibodies, the overall proportion with antibodies is lower compared with immunocompetent adults (moderate SoE for organ transplant patients and low SoE for patients with cancer or HIV). Prior infection provided substantial, sustained protection against symptomatic reinfection with the Delta variant (high SoE) and reduced the risk for severe disease due to Omicron variants (moderate SoE). Prior infection was less protective against reinfection with Omicron overall (moderate SoE), but protection from earlier variants waned rapidly (low SoE).
Limitation:
Single review for abstract screening and sequential review for study selection, data abstraction, and quality assessment.
Conclusion:
Evidence for a sustained antibody response to SARS-CoV-2 infection is considerable for both Delta and Omicron variants. Prior infection protected against reinfection with both variants, but, for Omicron, protection was weaker and waned rapidly. This information may have limited clinical applicability as new variants emerge.
Primary Funding Source:
Agency for Healthcare Research and Quality. (PROSPERO: CRD42020207098).
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