Coronavirus disease 2019 (COVID-19) spread worldwide in 2019, throwing many countries into economic crises as they attempted to control the spread of the disease with lockdowns, social distancing, and other restrictions. Mass vaccination schemes have begun to help bring the disease under control, but with variants of concern on the rise, worries for the elderly and immunocompromised have returned.
Some of the COVID-19 vaccines are mRNA vaccines. Traditionally, vaccines are made from inactivated/attenuated forms of the virus that allow the immune system to recognize viral surface proteins with little threat. However, suppose the inactivated virus reactivates, or an attenuated strain picks up new traits through horizontal gene transfer. In that case, the virus can again become a threat.
