Neutralizing Antibody Responses Elicited by Inactivated Whole Virus and Genetic Vaccines against Dominant SARS-CoV-2 Variants during the Four Epidemic Peaks of COVID-19 in Colombia

Abstract

Several SARS-CoV-2 variants of concern (VOC) and interest (VOI) co-circulate in Colombia, and determining the neutralizing antibody (nAb) responses is useful to improve the efficacy of COVID-19 vaccination programs. Thus, nAb responses against SARS-CoV-2 isolates from the lineages B.1.111, P.1 (Gamma), B.1.621 (Mu), AY.25.1 (Delta), and BA.1 (Omicron), were evaluated in serum samples from immunologically naïve individuals between 9 and 13 weeks after receiving complete regimens of CoronaVac, BNT162b2, ChAdOx1, or Ad26.COV2.S, using microneutralization assays. An overall reduction of the nAb responses against Mu, Delta, and Omicron, relative to B.1.111 and Gamma was observed in sera from vaccinated individuals with BNT162b2, ChAdOx1, and Ad26.COV2.S. The seropositivity rate elicited by all the vaccines against B.1.111 and Gamma was 100%, while for Mu, Delta, and Omicron ranged between 32 to 87%, 65 to 96%, and 41 to 96%, respectively, depending on the vaccine tested. The significant reductions in the nAb responses against the last three dominant SARS-CoV-2 lineages in Colombia indicate that booster doses should be administered following complete vaccination schemes to increase the nAb titers against emerging SARS-CoV-2 lineages.

Intensive Care during the COVID-19 Pandemic

“…Therefore, in response to the current pandemic, and in addition to non-pharmaceutical interventions (NPIs), such as social distancing, increased hand hygiene, and the wearing of surgical masks, vaccination is expected to be a safe and effective way to help build the immune barrier [ 10 , 14 , 15 , 16 , 17 , 18 , 19 ]. To date, there are more than 200 COVID-19 vaccine candidates in various stages of development, and more than 50 vaccine candidates have entered clinical trials, including the use of nucleic acids (DNA or RNA), inactivated or live attenuated viruses, viral vectors, and recombinant proteins or virus particles [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. However, there is a time lag between vaccine development and distribution in clinics.…”