President Trump will sign an executive order to temporarily suspend immigration into the United States. Air travel in the US has been negatively impacted by the COVID-19 pandemic. A Los Angeles county study finds that the number of adults with antibodies from coronavirus is higher than the number of cases that have been reported. Several states begin to lift lockdown restrictions. In New York, aggressive coronavirus antibody testing begins. Singapore, once seen as a model for its pandemic response, is now experiencing an uptick in COVID-19 cases. Coronavirus is one of many infectious diseases that has originated in domesticated or wild animals.