Experts say U.S. testing must double or triple to reopen safely

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Dr. Richard Besser tells Ali Velshi that “more work needs to be done” on antibody testing to ensure that Americans are protected from the virus as he stresses the importance in ramping up testing and contact tracing to keep sick people isolated as states reopen: “That kind of strategy can prevent the big outbreaks from occurring when we start to loosen some of the social distancing measures.”