The CDC is advising clinicians to use their judgment but suggests prioritizing testing for patients who show symptoms and are in the hospital, are age 65 and older or have chronic medical conditions. The agency also suggests prioritizing testing for anyone who develops symptoms within 14 days of being in contact with a person with a suspected or confirmed case of the illness or within 14 days of traveling from an affected area. If the illness is spreading within a community, that can also inform the decision about whether to test, the CDC has said.