Studies showed it decreased infection and transmission against the original strain of Covid.[0] It lost effectiveness against delta and then became nearly inef

Studies showed it decreased infection and transmission against the original strain of Covid.[0] It lost effectiveness against delta and then became nearly ineffective against Omicron (although still helping with reduction of hospitalizations and deaths). Non-mRNA vaccine is available now (Novavax) and the effectiveness, or lack thereof, seems similar. [0] https://med.stanford.edu/news/all-news/2021/07/vaccination-against-covid-19-prevents-breakthrough-infections.html https://med.stanford.edu/news/all-news/2021/07/vaccination-a...