Increasing Amount Of Infections With Coronavirus Variants. The Cases Of India And Brazil

 

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections caused more than 83 million known cases of coronavirus disease 2019 (Covid-19) by the end of 2020, but tremendous progress has been made with the authorization and deployment of vaccines and antibody therapies. These strategies are directed at the viral spike protein, but the emergence of viral variants, particularly in the S gene, threatens their continued efficacy.

 

These concerns have provided an impetus to increase testing and sequencing of viral DNA in infected persons in order to understand the transmissibility, virulence, and ability of variants to evade current vaccines. New York City has seen a troubling increase in viral variants. Most of these variants, which accounted for more than 72% of new cases as of March 30, 2021, were the B.1.1.7 variant first identified in the United Kingdom (in 26.2% of the cases) and the B.1.526 variant first identified in New York City (in 42.9%). Two areas of concern relate to the ability of variants to evade vaccine-induced immunity and cause asymptomatic infection (and thereby promote viral spread) or illness. Both consequences are important, both need to be considered independently, and both are largely unknown.

 

We describe two fully vaccinated persons in whom subsequent breakthrough infections with SARS-CoV-2 variants harboring a number of substitutions of interest developed. Despite evidence that the first dose of vaccine led to a strong antibody response to spike protein in Patient 1, saliva-based polymerase-chain-reaction (PCR) screening at Rockefeller University identified infection 19 days after the second dose (the booster vaccination). Testing was also positive for infection in Patient 2, who had completed vaccination 36 days previously. Together, these observations provide support for current strategies to monitor multiple variables proactively. These strategies include viral testing of symptomatic and asymptomatic persons, sequencing of viral RNA, and monitoring of neutralizing antibody titers, particularly in vaccinated persons who subsequently become infected.