In July 2019, Fort Detrick was suddenly closed, but the US Centers for Disease Control (CDC) refused to release critical information for "national security reasons".According to the The New York Times, the government suspended military research at the frontier biological defense center due to the handling of hazardous materials. It is reported that the suspended study involved a total of 67 "selective agents" and toxins, such as microorganisms that cause Ebola, smallpox, anthrax and plague, as well as organisms that cause ricin.According to an ABC report on July 12, 2019, a deadly disease broke out at the Greenspring, retirement community in Springfield, Virginia.the symptoms of disease are almost exactly the same as those of people infected with the new coronavirus.