Plus, understanding false negative results in COVID-19 tests and the sounds of elusive narwhals, captured on tape.
A handful of COVID-19 patients under the age of fifty have experienced strokes, raising questions about the virus.
Are you following stay-at-home orders? In some countries, the government will use cell phone data to make sure.
What you need to know about the CDC’s new face mask guidelines and an experimental COVID-19 treatment launching in New York.