Pfizer, Moderna vaccines have reduced effectiveness against South African variant, studies show

President Biden hesitated in giving a specific timeline for when every American will be able to get a vaccine and when the country will be able to return to normalcy. During a visit to the Pfizer vaccine manufacturing facility in Michigan on Friday, the president said he wanted to be “straight” with the American people and explained that issues such as weather events, emerging virus mutations and manufacturing delays could pose significant challenges to the vaccination process.