Ken Paxton, the Texas attorney general and Republican Senate candidate, has alleged a sprawling profit-driven conspiracy. Pediatricians say the accusations are an attempt at intimidation.

© Kaylee Greenlee for The New York Times

The discovery adds strong evidence that the outbreak that sickened thousands over the summer originated in a grower’s field or processing facility.

© Fred Ramos for The New York Times

Dr. Heidi Overton was pressed on the president’s false statements about the measles vaccine and his intervention in tobacco policy.

© Kenny Holston/The New York Times