Using levels of neutralizing antibodies (nAbs), we evaluate the successful Chilean SARS-CoV-2 vaccine campaign, which combines different vaccine technologies and heterologous boosters. From a population-based study performed in November 2021, we randomly selected 120 seropositive individuals, organized into six groups of positive samples (20 subjects each) according to natural infection history and the five most frequent vaccination schemes. We conclude that the booster dose, regardless of vaccine technology or natural infection, and mRNA vaccines significantly improve nAbs response.
Keywords: AZD1222; BNT162b2; COVID-19; CoronaVac; SARS-CoV-2; cross-sectional design; neutralizing antibodies; vaccine-preventable diseases; vaccines; viruses.