The third individual is an Irving resident in their 50s who recently traveled to an event out of state, according to the agency. They are being treated at a Dallas-area hospital.
"The city of Irving is currently monitoring the COVID-19 situation and have been in close contact with State and County officials in regard to the current situation in our area," Irving Mayor Rick Stopfer said in a statement. "We will continue to stay connected with public health officials and are prepared for the care and safety of our residents, businesses and visitors."
The first identified individual was a 77-year-old who frequently travels out of state and is being treated at a Dallas hospital, according to DCHHS. The second is in their 50s and was in close contact with the first identified individual. Dallas County will not release any other identifiable information about the three individuals.
A presumptive positive case means a patient has tested positive at a public health laboratory, but results are pending confirmation by the Centers for Disease Control and Prevention, according to the Centers for Disease Control and Prevention.
"While we know this case is concerning, it is not unexpected,” DCHHS Director Dr. Philip Huang said in a March 10 news release. "We have been watching the numbers increase across the US and have been preparing for this event. We are working with all local, regional, and statewide health authorities to monitor the situation and update the public."
County officials urged local residents to follow CDC guidelines on reducing the spread of the virus. That includes staying home when you suspect you are sick; covering your mouth and nose when sneezing or coughing with a tissue, and then disposing of the tissue; washing hands often with soap and water for at least 20 seconds; using alcohol-based hand sanitizer if a washing station is unavailable; and routinely cleaning handles, surfaces and objects.