By Justin Udo

PHILADELPHIA (CBS) — More than one million people in the United States have HIV, the virus that causes AIDS and, according to health officials, 1/5th of those people don’t know they are infected.

To help encourage all at-risk Americans to get tested, today is the 19th annual National HIV Testing Day.

Eric Paulukonis, the prevention services director at the Mazzoni Center, a health care provider in center city Philadelphia that offers wellness services in an LGBT-focused environment, says it’s a day created for people to learn their status, get treated if need be, and learn ways to stay healthy.

“The easiest way (to get tested) is to come in to one of the walk-in clinics that are stationed throughout Philadelphia, where you can come in and get an absolutely free HIV rapid test,” Paulukonis says.  “It takes about 20 minutes to get your results.”

Throughout the day today, the Mazzoni Center will have a mobile facility making stops around Philadelphia, giving out free tests.

This afternoon it will be at Broad and Girard from 12:30-3:30pm, and at 710 South 5th Street from 4:30-7pm.

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