First, surges in Covid-19 infections led to shortages of hospital beds and staff. Now it's oxygen

Hospitals in parts of the South are running out of oxygen supply as Covid-19 cases and hospitalizations continue soaring, driven by the swaths of people who remain unvaccinated and a dangerous coronavirus variant that has infected millions of Americans.

A respiratory therapist treats a COVID-19 patient in a NCH Healthcare System's ICU on August 9 in Naples, Florida.

Several hospitals in Florida, South Carolina, Texas and Louisiana are struggling with oxygen scarcity. Some are at risk of having to use their reserve supply or risk running out of oxygen imminently, according to state health officials and hospital consultants. With the continued uptick in Covid-19 cases, there has been more demand on the oxygen supply, and hospitals cannot keep up the pace to meet those needs, Donna Cross, senior director of facilities and construction at Premier -- a health care performance improvement company -- told CNN. "Normally, an oxygen tank would be about 90% full, and the suppliers would let them get down to a refill level of 30-40% left in their tank, giving them a three- to five-day cushion of supply," said Cross. "What's happening now is that hospitals are running down to about 10-20%, which is a one- to two-day supply on hand, before they're getting backfilled." Even when they're getting backfill, it's only a partial supply of about 50%, Cross said. "It is very critical situation."

Florida on Saturday had the highest Covid-19 hospitalization rate in the country, with 75 patients per 100,000 residents in hospitals with the virus, according to data from federal health officials and Johns Hopkins University. It also reached yet another pandemic high of Covid-19 cases Friday, reporting 690.5 new cases per 100,000 people each day from August 20 to August 26, state data showed.

Dr. Ahmed Elhaddad, an intensive care unit doctor in Florida, told CNN's Pamela Brown on Saturday that he's frustrated and "tired of seeing people die and suffer because they did not take a vaccine." He said the Delta variant is "eating" people's lungs, which eventually leads to their collapse. "We're seeing the patients die faster with this (Delta) variant," said Elhaddad, who is the ICU medical director at Jupiter Medical Center. A respiratory therapist treats a COVID-19 patient in a NCH Healthcare System's ICU on August 9 in Naples, Florida. "This round, we're seeing the younger patients -- 30-, 40-, 50-year-olds -- and they're suffering. They're hungry for oxygen, and they're dying. Unfortunately, this round they're dying faster," he said. The government's top infectious diseases expert, Dr. Anthony Fauci, told CNN's Jake Tapper that the US could see an additional 100,000 deaths from Covid-19 by December, as predicted by a University of Washington model. "What is going on now is both entirely predictable, but entirely preventable. And you know we know we have the wherewithal with vaccines to turn this around," Fauci, director of the National Institute of Allergy and Infectious Diseases, said. Elhaddad noted that his ICU does not have a single Covid-19 patient who is vaccinated, nor did he see any vaccinated people die from Covid-19. "There's no magic medicine. ... The only thing that we're finding is that the vaccine is preventing death. It's preventing patients from coming to the ICU," Elhaddad said. Fauci pointed to the 80 million Americans who are eligible for the vaccine, but who are not vaccinated. "We could turn this around and we could do it efficiently and quickly if we just get those people vaccinated," he said.

Florida has fully vaccinated 52.4% of its total population, data from the US Centers for Disease Control and Prevention showed Saturday. Meanwhile, less than 50% of people in South Carolina, Louisiana and Texas -- where oxygen supplies are also low -- are fully vaccinated. Studies have shown that full vaccination is necessary for optimal protection against the Delta variant. Nationally, 52.1% of the population was fully vaccinated as of Saturday, CDC data shows.