NEW YORK (AP) — U.S. health officials are explaining why they recently shortened their COVID-19 isolation and quarantine recommendations. They also clarified that the guidance applies to school kids as well as adults. However, the Centers for Disease Control and Prevention maintained that, for people who catch the coronavirus, testing is not required to emerge from five days of isolation. The CDC released the documents Tuesday. Agency officials previously said the changes were in keeping with evidence that people with the coronavirus are most infectious in the two days before and three days after symptoms develop.