covid-19July 28, 2020 Pfizer and BioNTech begin large-scale trial of coronavirus vaccine in the United States Drug giant Pfizer and its partner BioNTech have begun an advanced trial of one of their experimental coronavirus vaccines in volunteers in the United States. Related posts U.K.'s Johnson launches mass testing…Do you need a Covid-19…What's behind workers' hesitation to…Fully vaccinated people can travel…Younger Latino men are Covid's…Salmonella infections in eight states…Salmonella infections in eight states…The U.S. isn't losing to…Virus-killing robot tested for use…In Covid fight, Cuba touts…