Health and Science

Watch live: NIH director and U.S. surgeon general testify on coronavirus vaccines

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National Institutes of Health Director Dr. Francis Collins and U.S. Surgeon General Dr. Jerome Adams are testifying Wednesday before the Senate Committee on Health, Education, Labor and Pensions on coronavirus vaccines.

The U.S., as part of the Trump administration's Operation Warp Speed initiative, has invested billions in six potential vaccines, including ones from Moderna, Pfizer and AstraZeneca, which have all started late-stage testing. U.S. health officials expect to find a safe and effective vaccine by the end of the year. 

The hearing comes a day after AstraZeneca announced that it was pausing its late-stage trial after a "suspected serious adverse reaction" in a participant in the United Kingdom.

It also comes as infectious disease experts and scientists have said they worry the vaccine approval process in the U.S. could be polluted by politics, not science.

The CDC has asked governors and health departments to prepare to distribute a vaccine as soon as Nov. 1, just two days before the election. Dr. Stephen Hahn, commissioner of the Food and Drug Administration, has also said the agency is prepared to bypass the full federal approval process in order to make a vaccine available as soon as possible.

Read CNBC's live updates to see the latest news on the Covid -19 outbreak.