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The director of the National Institutes of Health, Dr. Francis Collins, and US Surgeon General Dr. Jerome Adams testified before the Senate Health, Education, Labor and Pensions Committee on coronavirus vaccines Wednesday.
The U.S. has invested billions in six potential vaccines, including those from Moderna, Pfizer, and AstraZeneca, all of which have started late-stage testing as part of the Trump administration's Operation Warp Speed initiative. US health officials expect to find a safe and effective vaccine by the end of the year.
The hearing takes place the day after AstraZeneca announced that the trial will be suspended in the late stages following a "suspected serious adverse reaction" to a participant in the UK.
Infectious disease experts and scientists have said they fear that politics, not science, could pollute the US vaccine approval process.
The CDC has asked governors and health departments to prepare to hand out a vaccine two days before the election. Dr. Stephen Hahn, Commissioner for the Food and Drug Administration, also said the agency is poised to bypass the full federal approval process in order to make a vaccine available as soon as possible.
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