Dr. Fauci ‘cautiously optimistic’ about a coronavirus vaccine as testing troubles worsen

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Dr. Anthony Fauci says that he is “cautiously optimistic” about a coronavirus vaccine. But in the meantime, the virus is spreading faster than ever in the U.S., and testing sites across the country are being overwhelmed. Another big worry: hospital capacity. NBC’s Tom Costello reports for TODAY from Washington, D.C.