CAGUAS, PUERTO RICO (PIX11) — More than 10 years before people became ravaged by fentanyl and xylazine – moving like “living zombies” – in Philadelphia, Gladys Nieves Vazquez saw the same scenes in Puerto Rico.

“It was our reality,” Nieves Vazquez told PIX11 News on Friday. “It was not strange for me to see that.”

At one point, xylazine, the animal tranquilizer that users call “tranq,” was present in 80% of the illicit heroin, cocaine and fentanyl injected by drug users in Puerto Rico.

Nieves Vazquez, who works with a harm reduction group on the island, saw the skin ulcers that can lead to amputations before an apparent decrease in xylazine use because of the unsightly, painful abscesses it caused. Now, though, she’s worried about xylazine again, because she’s seen a return of severe skin lesions among her clients.

Nieves Vazquez is the executive assistant with El Punto en la Montana, an organization that brings clean needles, food, and Narcan to drug users in the central mountain region of the island. She said the zombie scenes were more concentrated in cities like San Juan.

“They are not afraid of mixing drugs,” Nieves Vazquez said of the users in Puerto Rico. “Participants mostly use cocaine and heroin together,” a dangerous concoction called a speedball.

Nieves Vazquez said three participants in her program died in the last year after fast-moving skin infections, some of them leading to amputation. She mentioned one client who had an infection on his arm that progressed rapidly within a week.

“It was already covering most parts of his arm,” Nieves Vazquez said. “And months later, he had to receive an amputation.”

The client later died.

Nieves Vazquez said she had spoken to a researcher working for the University of Nebraska in a San Juan-based project about testing for the presence of xylazine in the drug supply.

“The test for xylazine is not currently available to them,” she said.

Meanwhile, overdose prevention experts in New York are concerned about the new presence of xylazine in the city’s drug supply. Recent testing showed it was present in about 20% of samples.

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