By Nikhila Natarajan New York, Nov 18 : The US Food and Drug Administration (FDA) has green-lighted emergency use of the first at-home rapid coronavirus test that promises to expand testing options for Americans beyond the typical medical facilities and urgent care centers which have seen persistent delays in turnaround times. FDA on Tuesday gave emergency authorization to a 30-minute test kit from California-based Lucira Health. The test works by swirling a self-collected sample nasal swab in a vial that is then placed in the test unit. In 30 minutes or less, the results can be read directly from the test unit's light-up display that shows whether a person is positive or negative for the SARS-CoV-2 virus. The test is currently authorized for prescription use only. It has been okayed for home testing in people 14 and older. The bulk of testing in the US continues to be done by health professionals and then processed at laboratories. This news comes even as all 50 US states are experiencing "aggressive community spread", according to an internal White House report that leaked on Tuesday. The US leads the world in coronavirus cases and deaths. The virus is blamed for more than 248,000 deaths since it entered the country on January 21, 2020. /IANS