National Institutes of Health Director Dr. Jay Bhattacharya speaks during a meeting to sign an executive order about vaccines, Monday, Aug. 10, 2026, in the Oval Office of the White House in Washington. (AP Photo/Jacquelyn Martin)

Health and Human Services Secretary Robert F. Kennedy Jr. speaks during a meeting to sign an executive order about vaccines, Monday, Aug. 10, 2026, in the Oval Office of the White House in Washington. (AP Photo/Jacquelyn Martin)

President Donald Trump listens during a meeting to sign an executive order about vaccines, Monday, Aug. 10, 2026, in the Oval Office of the White House in Washington. (AP Photo/Jacquelyn Martin)

Health and Human Services Secretary Robert F. Kennedy Jr. speaks as President Donald Trump listens during a meeting to sign an executive order about vaccines, Monday, Aug. 10, 2026, in the Oval Office of the White House in Washington. (AP Photo/Jacquelyn Martin)

President Donald Trump holds up an image taken from his Truth Social account as Health and Human Services Secretary Robert F. Kennedy Jr. watches during a meeting to sign an executive order about vaccines, Monday, Aug. 10, 2026, in the Oval Office of the White House in Washington. (AP Photo/Jacquelyn Martin)

FILE - Dean Malcom drinks water while wiring street lights in extremely hot weather July 14, 2026, in Detroit. (AP Photo/Paul Sancya, File)

FILE - Simone Mosley waits for their ride in shade at a bus stop during an extreme heat warning July 13, 2026, in Minneapolis. (AP Photo/Ellen Schmidt, File)

FILE - Daniel Aragonez leaves a cooling center in Los Angeles, July 31, 2026. (AP Photo/Jae C. Hong, File)