NEW HYDE PARK, N.Y. (CBSNewYork) — According to the CDC, more than 2,400 people have been hospitalized with lung injuries linked to vaping and about 50 people have died.

Most patients reported using products that contain THC, a marijuana ingredient that’s not legal but very popular. Gregory Rodriguez is one of those patients.

“I just was thinking about wow, you know, I almost died,” Rodriguez told CBS2’s Jessica Layton.

When Rodriguez started getting sick at the end of the summer, it felt like the flu.

“Feeling very hot,” he said. “Stomachache … diarrhea.”

But the flu doesn’t last for five weeks, and by the middle of September, his symptoms were unbearable.

“It got to the point where I could not breathe,” Rodriguez said.

Scared to tell doctors he’d been vaping THC, which is illegal, the 22-year-old from Queens had no choice but to go to the ER.

“The doctor says to my mom, ‘Your son is very, very, very, very sick,'” Rodriguez said.

Dr. Zubair Hasan says when he saw Rodriguez, he thought, “He’s going to die. If he gets any worse, he’s going to die … We very quickly realized this was all related to vaping and to these lung injuries.”

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Hasan says so far, doctors at Long Island Jewish Medical Center have treated about 40 patients with vaping-related illness. Rodriguez was the sickest they’ve seen.

“His oxygen levels were dangerously low and there was not much more that could be have been done for him on a ventilator alone. He needed to be put on this lung bypass machine to give him a shot at survival,” Hasan said.

“I just didn’t want to believe that it was the vapes,” he said.

That’s because for two years, it was the one thing that really helped him handle his anxiety.

“I decided to try out buying THC carts in bulk on an encrypted site on the dark web,” Rodriguez said.

Doctors have linked a number of vaping-related illnesses and deaths to THC and vitamin E acetate, used to dilute THC oil, which when heated and inhaled can cause a chemical burn in the lungs.

“It’s going unregulated and we just don’t know what’s going into these products,” Hasan said.

RELATED STORY: CDC Says Most Sickened By Vaping-Related Illnesses Used THC Products

Rodriguez’s lungs have healed significantly, but it’s too early to know if there is permanent damage.

Monday marks three months since Rodriguez left the hospital. Now that his health is getting back on track, he’s focused on a career in computer science, completely free from vaping.

“I see it as a second chance … I’m meant to do something with my life,” he said.

That includes being honest about the dangers of this popular habit that he believes nearly put him on his death bed.