Moderna and Merck announced their personalized cancer vaccine showed promise in a late trial. Stock prices climbed for both companies. Moderna stock surged 177 percent. Short sellers lost an estimated 5.5 billion dollars. The Times said Moderna intends to be a cancer-focused company.
Federal health rules shifted. The Trump administration ordered separate MMR shots. South Carolina health officials advised parents to vaccinate children before school due to a past measles outbreak. Douglas County reported a big drop in kid shot program participation. The Washington Post reported on federal vaccine fights and answered reader questions.