Moderna and Merck said their personalized cancer vaccine demonstrated potential in a late trial. Stock prices went up for both companies. Moderna stock rose 177 percent. Short sellers forfeited an estimated 5.5 billion dollars. The Times said Moderna aims to be a cancer-focused company.
Federal health rules were updated. The Trump administration ordered separate MMR shots. South Carolina health officials instructed parents to vaccinate kids before school due to a past measles outbreak. Douglas County reported a big drop in childhood immunization program participation. The Washington Post reported on federal vaccine fights and addressed reader questions.