A single dose of Pfizer or Moderna’s Covid-19 vaccine was 80% effective in preventing infections. This is what emerges from a new study by the Centers for Disease Control and Prevention (CDC) on vaccinated healthcare workers. The effectiveness of partial immunization was observed two weeks after the first dose, according to the CDC, which surveyed nearly 4,000 healthcare workers, first responders, and first-line workers between December 14 and March 13.
“Two doses are better than one,” notes the CDC, adding that vaccine effectiveness jumped to 90 percent two weeks after the second dose.
“These results indicate that licensed COVID-19 mRNA vaccines are effective in preventing SARS-CoV-2 infection, regardless of symptom status, among working-age adults under real-world conditions,” the US agency wrote in study. “COVID-19 vaccination is recommended for all eligible individuals.”