"Garry died this morning about 9:30 as a result of the damage COVID-19 did to his lungs and body," Jeff Wacha said in a social media post.
Bowie was the executive director of Being Alive, whose stated mission is "to end HIV by ending stigma, engaging people in wellness, removing barriers to care, and restoring dignity."
In a Facebook post that has received hundreds of condolences in response, Wacha said Bowie began exhibiting flu-like symptons on March 19.
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Bowie declined to go to a hospital after "his breathing became shallow and rapid" on March 27, according to his husband, who called an ambulance the following morning after Bowie's condition did not improve.
Arriving paramedics immediately administered oxygen to Bowie.
"I was able to exchange just a few words to him before they shut the doors and left with him," Wacha said. "I told him how much I loved him, and he told me how much he loved me. It was the last time I would see him."
The two men spoke with each other by phone while Bowie as in the emergency room, where he was diagnosed with pneumonia and acute respiratory distress syndrome, or ARDS. He was later sedated, intubated and placed on a ventilator.
"I had no idea it would be the last time I spoke to my husband, my reason for living, the man who has supported me emotionally the previous 20 years and kept me alive, the man who made me laugh every day that we were together," Wacha said.
According to Being Alive's website, the 34-year-old organization focuses on the mental health and wellness of people living with HIV and AIDS. Its no-cost services include "comprehensive emotional support, treatment education, prevention, advocacy, wellness and social services."