The CDC Reports That COVID-19 Vaccine Effectiveness is Declining
Two new studies from the Centers for Disease Control and Prevention show fully vaccinated Americans’ immunity to Covid-19 is waning as the more-transmissible Delta variant continues to spread across the country.
One study, which focused on frontline health care workers, found that vaccine effectiveness declined by nearly thirty percentage points since the Delta variant became the dominant strain in the U.S. The analysis also concluded that the Covid-19 vaccines were 80 percent effective in preventing infection among the frontline health care workers.
The CDC cautioned in its report that the vaccine effectiveness “might also be declining as time since vaccination increases and because of poor precision in estimates due to limited number of weeks of observation.”
