COVID-19 vaccines are safe and effective at preventing COVID-19, including severe illness and death. COVID-19 vaccines can reduce the risk of people spreading COVID-19. COVID-19 vaccines are effective against variants of the virus that causes COVID-19, currently circulating in the United States including the Delta variant. People with weakened immune systems, including people who take … Continue reading What we know about the COVID-19 vaccines (from CDC 8/16/2021)