Seven new cases of HIV were reported in the Boston area, mostly last month, among homeless people who inject drugs. To prevent further transmissions, public health officials launched an investigation and alerted health officials in the Boston area this week, The Boston Globe reports.

In the past year, 25 people who inject drugs and have experienced homelessness tested positive for HIV and sought care in Boston.

“It’s another wake-up moment for us all,” Kevin Cranston, director of the state health department’s Bureau of Infectious Disease and Laboratory Sciences, told the newspaper. “Even a relatively small cluster in this population has great potential to expand to new cases.”

Massachusetts has increased its harm reduction efforts, pushing the number of needle exchanges from five to 33 in the past five years, though only two are located in Boston.

The state recently experienced an HIV outbreak:182 people contracted the virus in Lowell and Lawrence between 2015 and 2019. Transmissions dropped after health officials made an effort to test and treat people and improve prevention services. For details, see “Why the Bay State Worries About a Possible HIV Outbreak.”

Last summer, Boston was one of 10 metropolitan areas to receive a federal HIV grant. For more, read “These 10 U.S. Cities Just Got Nearly $100K Each to End HIV.”