Health experts are now encountering a rare and terrifying COVID-19 complication: plug-like blood clots in the limbs of coronavirus victims that strangle circulation.
And that means you could lose a limb to COVID-19, even if you don't lose your life.
After querying 10 major hospital networks in Florida, the South Florida Sun Sentinel has found 26 previously unreported examples of these coronavirus-caused limb clots. These clots contributed to the death of at least six of the patients who had them.
And in at least one instance, surgeons at the University of Miami report having to amputate the leg of a Miami-Dade man in his mid-50s who lost circulation to the limb after contracting the virus.
Health laws bar the release of more information about the man who lost his leg, and data is scarce on amputations in Florida since the pandemic started. A spokesman for Florida's Agency for Health Care Administration, which keeps track of amputated limbs, says they don't expect to have clear statistics about amputations until April next year because of the way that hospitals report data on the procedure.
And doctors say they still don't understand how or when or why the virus causes these clots.
"We still don't know what ... it does," Dr. Mohammad Abdallah, a vascular surgeon with Broward Health, said of the virus.
But the story of how David Guerrero, an otherwise healthy 48-year-old Fort Lauderdale airport worker, almost lost his right leg to the virus serves as a chilling reminder of the potential costs of our learning curve with this new disease.
Guerrero wasn't even sure if he had COVID-19 when he started losing feeling in his right foot.
During the third week of July, he "started to feel pins and needles" in his extremity.
Three weeks earlier, Guerrero -- who doesn't smoke and doesn't have any preexisting conditions -- had come down with what he thought was a bad stomach bug. But the gastrointestinal symptoms persisted for a suspiciously long time. His doctor recommended a COVID-19 test, but the results hadn't come back yet when Guerrero's foot started to go numb.
Soon, Guerrero couldn't walk. It was the weekend, so he tried to hold off on calling the doctors, but the pain became unbearable.
"I tried to sleep, I took a hot shower, I felt terrible. Man, I felt terrible," he said.
So Guerrero checked himself into the emergency room at Broward Health, and that's when medical professionals told him he was in danger of losing his leg.
"There was no blood getting into his foot," said Abdallah, who was Guerrero's vascular surgeon. He and his medical partner, both vascular surgeons with Broward Health, have seen at least six patients with limb-threatening clots related to COVID-19 since the start of the pandemic.
Abdallah suspected COVID-19 was the culprit behind Guerrero's clot, and while he was in the emergency room, Guerrero's coronavirus test came back positive, almost two weeks after he took it. An X-ray showed also showed evidence of infection in Guerrero's lungs.
"His chest X-ray was classic for COVID," Abdallah said.
Abdallah decided to put Guerrero on powerful intravenous blood-thinners to try to bust the clots. But after three days of blood thinners did nothing to the clots, Abdallah told Guerrero they were going to have to go in and bust the clots by hand.
"At this point he didn't have much to lose. His limb was going to go if we left it alone, and if we intervened there was a possibility he'd keep it." Abdallah said.
What the vascular surgeon found inside the arteries of Guerrero's leg surprised him.
"It was like a plug almost," Abdallah said of the hard, black clots he removed by hand. "It was pretty extensive."
Dr. Jorge Rey, chief of vascular surgery at the University of Miami School of Medicine, said the vascular surgeons at his hospital network have treated 20 patients with symptoms similar to Guerrero's.
Rey said doctors can often save the arms and legs of younger people, but he said the appearance of the clots -- called "acute limb ischemia" -- in older, sicker folks often heralds the onset of death.
"If the acute limb ischemia is the first symptom, which we have seen a few, then those patients do well," Rey said. "If it happens after, as a complication, then they definitely died. We can count at least six patients that died."
Both Rey and Abdallah say that clinicians do not yet fully understand how the virus is causing these blood clots and that they do not only occur in the limbs, but rather all over the body, sometimes resulting in heart attacks and, in other instances, leading to strokes.
It is unclear if clotting condition is related to any other pre-existing conditions, such as diabetes or heart disease. At least two of the 26 individuals were otherwise healthy people, and data on pre-existing conditions for the other 24 was not immediately available.
"What is the molecular mechanism? No one knows yet," Rey said.
Rey notes that he's found no evidence of virus in people's blood when they get the clot, meaning that the clots are likely triggered by the human immune system itself.
One thing is clear, though: Clinicians still have much to learn about how SARS-COV-2, the virus that causes COVID-19, interacts with the human body, and in some cases triggers incredibly powerful and potentially life- and limb-threatening responses from the immune system.
Guerrero said he is just happy that the virus didn't cost him his leg below the knee.
"Man, I'm forever grateful to Dr. Abdallah."