WASHINGTON -- The Army is taking the necessary steps to combat the spread of COVID-19, all while simultaneously implementing measures to treat personnel impacted by the disease, the Army's top medical officer said Thursday.With the emerging concern over the spread of COVID-19, the safety and health of all service members have become one of DOD's top priorities, said Thomas McCaffery, the assistant secretary of defense for health affairs.According to data collected on March 4, four people have tested positive for the novel coronavirus throughout the Department of Defense, McCaffery said, as he testified with other defense health officials before the House Committee on Appropriations' defense subcommittee.One Soldier and two dependents stationed in South Korea were among the four that recently tested positive for the virus, said Lt. Gen. Scott Dingle, the Army surgeon general.Twelve others throughout the DOD are "suspected" to have the virus and are awaiting results, added McCaffery. In support, the department has distributed "force health protection guidance," based mostly on information provided by the Centers for Disease Control and Prevention.COVID-19 can be spread from person-to-person, either through close contact, or through contact with "respiratory droplets" that can be produced after a person coughs or sneezes, according to information on the CDC's website. People tend to be the most contagious when they are symptomatic. However, there are reports of COVID-19 spreading before a person shows symptoms.The released DOD guidance outlines proper health-care worker protection, along with ways to screen and report a patient when the virus is detected, McCaffery said. The documents also identify ways to self-protect against the virus, which includes proper hygiene practices.The military health system is part of a broader interagency approach to combat COVID-19, McCaffery said. This ongoing joint initiative, which includes the CDC and National Institute of Health, is working to develop a COVID-19 vaccine, along with a separate anti-viral therapy.It will take months before a vaccine starts the clinical trial process, he added. Once a vaccine moves past its trial phase, the Food and Drug Administration will start its research and analysis process, which could take several years to complete."Similarly, (with the) anti-viral therapy, we might be closer in terms of having something usable. It is actually in clinical trials right now and testing for efficacy," he said.Coinciding with the DOD's methodology, the Army is taking a "three-pronged approach to prevent, detect, and treat," COVID-19, Dingle said."Prevention is the education awareness of all the Soldiers and family members within an installation commander's or senior commander's footprint," Dingle said. "The detection piece (includes) screenings, that we are doing … to verify the presence," of the disease.If the virus were to spread, the Army stands ready, having "pandemic response plans" at all installations, Dingle added.The best way to prevent the illness is to avoid exposure, according to the CDC. In South Korea, leaders have already released guidance to limit the mass congregation of personnel, Dingle said.And while operations continue in the area, Soldiers and families are also reminded to avoid contact with people that are sick, and to avoid touching their eyes, ears and nose. Further, common use areas and items should be frequently sanitized.