NEW YORK — Everyone in the United States ages 15 to 65 should be screened at least once for HIV, the virus that causes AIDS, a medical advisory group to the government has recommended.

Early identification and treatment are crucial for preventing the virus’s spread and lengthening the lives of those who are infected, according to the draft guidelines released this week by the US Preventive Services Task Force. Previously, screening focused on people in high-risk groups and pregnant women. That recommendation was made in 2005.