WASHINGTON — President Joe Biden has tested positive for COVID-19 for a second time, the White House said Saturday. According to White House physician Dr. Kevin O’Connor, the President “has experienced no reemergence of symptoms, and continues to feel quite well.” Biden, 79, will not have more treatment but will resume isolation after the “rebound case,” the White House said. Biden will follow Centers for Disease Control and Prevention guidelines and will remain in isolation for at least five days. The White House canceled Biden’s planned trip to his home in Wilmington, Delaware, on Sunday, and a visit to Michigan on Tuesday.