Pressure to create a coronavirus vaccine is increasing by the day, but for a safe vaccine to enter the market, it takes time.
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WHO Director-General Tedros Adhanom Ghebreyesus on Wednesday declared the coronavirus outbreak a pandemic as the global death toll rose above 4,300 and the number of confirmed cases exceeded 121,000.
"We have rung the alarm bell loud and clear," Tedros said at a news conference. "We cannot say this loudly enough, or clearly enough, or often enough: All countries can still change the course of this pandemic."
The U.S. death toll climbed to 31 and the number of U.S. cases rolled past 1,000, federal health officials said. Centers for Disease Control and Prevention Director Robert Redfield told a congressional committee the virus has spread to at least 38 states.
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