COVID-19 Vaccines: Cardiovascular Perspectives

COVID-19 Vaccines

Abstract

The accelerated development of COVID-19 vaccines has ushered in new hope for the beginning of the end of this unprecedented pandemic with the heaviest toll on global health and economy. The goal of vaccination is to achieve “herd immunity” which helps interrupt the chain of transmission with the threshold of such immunity estimated at 60-70%. There are four main types of COVID-19 vaccines: messenger RNA (mRNA); viral vector; protein-based; and whole virus. mRNA vaccines and most of the COVID-19 vaccines are using various versions of the spike (S) protein as their vaccine antigen component, while a few vaccines employ the whole virion. Local reactions and mild symptoms are the most common adverse reactions to vaccination; however, anaphylaxis is a potentially life-threatening adverse effect and needs to be monitored and promptly managed. Deaths with temporal association with vaccination have also been reported, but not causally linked to vaccination. Thrombotic events have also been reported, particularly with two brands, and have caused alarm but apparently remain extremely rare, nevertheless authorities remain watchful. One is considered fully vaccinated for COVID-19 ≥2 weeks after one has received the last dose. Unfortunately, new strains of COVID-19 are emerging fast, for which the current vaccines may be less effective. Thus, it is still crucial to continue wearing facemasks, apply hand washing, and social distancing in order to slow viral spread and to protect everybody from infection. Several unknowns still remain about COVID-19 vaccines that relate to the safety and efficacy of the vaccines in “special” populations, the degree and duration that these vaccines protect against infection and transmission. and possible long-term adverse effects of vaccination, not yet encountered in phase 3 trials. Rhythmos 2021;16(2): 22-33.