Neutralizing Antibodies as Predictors of Vaccine Breakthrough Infection in Healthcare Workers Vaccinated with or without a Heterologous Booster Dose: A Cohort Study during the Third COVID-19 Wave in Peru

Abstract

We evaluated neutralizing antibody (NAbs) levels as a protective factor against vaccine breakthrough infection (VBI) in healthcare workers (HCWs) during the third COVID-19 wave in Peru. This retrospective cohort study employed the information from a private laboratory in Lima (Peru) of HCW who received only two BBIBP-CorV vaccines or (additionally) a heterologous booster with BNT162b2. We evaluated the association between the VBI and the levels of NAbs at 21, 90, 180, and 210 days after the BBIBP-CorV second dose. NAbs were calculated with the cPass™ SARS-CoV-2 Neutralization Antibody Detection kit (surrogate virus neutralization test (sVNT)) and the Elecsys® anti-SARS-CoV-2 S Test. Of the 435 HCW evaluated, 31.72% had an infection previous to vaccination, 68.28% received a booster dose, and 23.21% had a VBI during the third wave. The variables associated with a lower risk of VBI were male sex (aRR: 0.43) and those who had (180 days after BBIBP-CorV inoculation) NAbs levels ≥ 60% (aRR: 0.58) and ≥90% (aRR: 0.59) on cPass™, and ≥500 with Elecsys® (aRR: 0.58). HCW whose NAbs persisted at higher levels six months after the BBIBP-CorV showed a lower risk of suffering from a VBI during the third COVID-19 wave.

Vaccine Based on Recombinant Fusion Protein Combining Hepatitis B Virus PreS with SARS-CoV-2 Wild-Type- and Omicron-Derived Receptor Binding Domain Strongly Induces Omicron-Neutralizing Antibodies in a Murine Model

“…It has been previously reported that high levels of RBD-specific IgG are correlated with high VNTs toward the SARS-CoV-2 wild-type strain [ 24 , 33 ] and that hu-1-induced antibodies partly cross-react with variants of concern [ 15 , 24 , 34 ]. However, functional assays, such as virus neutralization assays or molecular interaction assays, are especially useful for the measurement of antibodies protecting against virus infection [ 12 , 35 , 36 ]. Therefore, serum samples obtained from mice six weeks after the third immunization with the PreS-RBD fusion constructs were analyzed regarding their capacity to neutralize SARS-CoV-2 Omicron ( Figure 6 ).…”

Humoral Response after a Fourth Dose with mRNA-1273 in Healthcare Workers with and without a History of SARS-CoV-2 Infection and Previously Vaccinated with Two Doses of BBIBP-CorV Plus BNT162b2 Vaccine

“…Most of these mutations fail to alter their structure, but some can alter their sequencing and the composition of amino acids in essential proteins, which could give rise to new variants. Currently, multiple variants are circulating worldwide, many with mutations that decrease the effectiveness of vaccines against COVID-19, even with high NAbs titers [ 37 , 38 , 39 ]. The emergence of these variants has motivated the use of bivalent vaccines, which the Food and Drug Administration (FDA) has approved for the immunization of patients older than six months in the case of the Moderna vaccine and patients older than five years with the Pfizer-BioNTech vaccine [ 40 ].…”