Pfizer-BioNTech said Wednesday they will supply the United States with an additional 100 million doses of its coronavirus vaccine as the country struggles to contain surges in infections.The drug makers said they expect to complete the delivery by the end of July in a nearly $2 billion deal with the federal government.“Securing more doses from Pfizer and BioNTech for delivery in the second quarter of 2021 further expands our supply of doses across the Operation Warp Speed portfolio,” Health and Human Services Secretary Alex Azar said in a statement. “This new federal purchase can give Americans even more confidence that we will have enough supply to vaccinate every American who wants it by June 2021.”On December 11, the U.S. Food and Drug Administration approved the Pfizer-BioNTech vaccine for emergency use, clearing the way for the drug makers to supply the government with an initial 100 million doses.The agreement announced Wednesday stipulates the companies will deliver at least 70 million of the additional doses by June 30, with the remaining 30 million doses being delivered by July 31. The government can also purchase up to an additional 400 million doses.The Pfizer-BioNTech vaccine was the first of two to be approved for emergency use by the Food and Drug Administration, the other developed by rival Moderna, Inc. The first shipments of the Pfizer-BioNTech vaccine throughout the U.S. began December 13.The U.S. continues to lead the world in COVID-19 deaths, with nearly 323,000, and in infections, with more than 18.2 million, according to Johns Hopkins University. The coronavirus causes the COVID-19 disease.Health care workers and nursing home residents have been among the first to be vaccinated. More than 600,000 people in the U.S. received their first doses as of Monday, according to the U.S. Centers for Disease Control and Prevention.Both the Pfizer-BioNTech and Moderna vaccines require two shots to be fully effective. 
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