In this handout photo released by the University of Oxford samples from coronavirus vaccine trials are handled inside the Oxford Vaccine Group laboratory in Oxford, England Thursday June 25, 2020. Scientists at Oxford University say their experimental coronavirus vaccine has been shown in an early trial to prompt a protective immune response in hundreds of people who got the shot. In research published Monday July 20, 2020 in the journal Lancet, scientists said that they found their experimental COVID-19 vaccine produced a dual immune response in people aged 18 to 55. (John Cairns, University of Oxford via AP)
Samples of the University of Oxford coronavirus vaccine trials are handled at a laboratory. AP

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