In the past week, three black trans women have been shot and killed in the U.S. and at least 19 have been murdered this year alone.

Parkland shooting survivor David Hogg has spoken out against the epidemic of anti-transgender gun violence in America.

Hogg was a featured speaker at the U.S. Conference on AIDS, an annual meeting of experts in the field of prevention, treatment, and the search for a cure for the disease, held this year in Orlando, Florida.

The gun control activist tweeted out a picture of himself on stage holding a hand fan with the transgender Pride flag colors, upon which was written, “End Trans Gun Violence.”

Thank you so much to the US conference on AIDS for inviting me to come and speak! If you’re not aware of how the #transgender community is affected by gun violence please check out this website https://t.co/VlGEmSXonK pic.twitter.com/mUBGvRNVfT — David Hogg (@davidhogg111) September 6, 2018

Hogg encouraged those interested in learning more about the issue to visit HRC’s article remembering those lost this year, a post which also links to the organization’s guide to reporting on the transgender community.

“At least 19 transgender people have been killed in the U.S. this year,” tweeted HRC President Chad Griffin, who thanked Hogg for speaking out. “Over the past week, at least three Black trans women have been killed by gun violence. The time for gun safety reform is now.”

On August 30, two black transgender women were shot and killed: 24 year-old Dejanay Stanton in Chicago, and 18 year-old Vontashia Bell in Shreveport, Louisiana.

This week, Shantee Tucker, who just turned 30, was shot and killed in Philadelphia.

The transgender community also faces challenges when it comes to the battle against HIV/AIDS, including a need for more research on how the population is uniquely affected.