People sit in the observation area after some received doses of the Pfizer COVID-19 vaccine at a three-day vaccination clinic at Providence Wilmington Wellness and Activity Center on July 29, 2021 in Wilmington, California. Providence is ramping up vaccination efforts especially among communities of color as COVID-19 cases are escalating across Southern California. (Photo by Mario Tama/Getty Images)

The Delta variant is wreaking havoc through much of the United States, but the "silver lining" is that more Americans appear to be at the tipping point of understanding the importance of Covid-19 vaccinations, one expert said.

"People are waking up to this," Director of the National Institutes of Health Dr. Francis Collins told CNN Sunday. "That's what desperately needs to happen if we are going to get this Delta variant put back in its place, because right now it is having a pretty big party in the middle of the country."

In the past two weeks, daily case rates have gone up four-fold, Collins said. This increase comes as the Delta variant spreads and the percentage of vaccinated Americans hovers around 49.6%, according to the US Centers for Disease Control and Prevention. Hospitals are once again filling up with patients as the virus tears through the unvaccinated population.

Experts say the path to protect Americans and slow or stop the spread of the virus is clear: vaccinations. More than 99.99% of people fully vaccinated against Covid-19 have not had a breakthrough case resulting in hospitalization or death, according to the latest data from the CDC.

And though vaccination rates have slowed since the initial rush for inoculation, as the pandemic once again worsens, the rates are climbing.

On Saturday, more than 816,000 doses of Covid-19 vaccine were administered across the US, marking the fifth straight day more than 700,000 shots in arms were recorded, according to the CDC. The current seven-day average of doses administered is 662,529 per day, the highest average since July 7.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, attributed the increase to two likely factors: trusted leaders coming out in support of vaccines and people seeing how much better vaccinated communities are faring against the virus, he told CBS Sunday.

In Florida, where nearly 1 in 5 new Covid cases across the US are reported, chief clinical officer for AdventHealth Central Florida, Dr. Neil Finkler, said none of his patients thought they would get the virus.

"The Delta variant has proven to be so highly contagious that even the young and the healthy, including pregnant patients, are now starting to fill up our hospitals," said Finkler.

The race to get people vaccinated

Despite the rising number of Covid-19 cases, Fauci told ABC Sunday that he believes there is enough community protection to prevent the country from having to implement lockdown measures again.

"I think we have enough of the percentage of people in the country, not enough to crush the outbreak, but I believe enough to not allow us to get into the situation we were in last winter," he said.

But things are still likely to get worse for the unvaccinated, Fauci warned.

"We're looking to some pain and suffering in the future because we're seeing cases go up," he told ABC.

And while it is the unvaccinated that will likely experience the brunt of this pain and suffering, Fauci noted the choices of the unvaccinated impact the overall community situation.

"When you have unvaccinated people getting infected, you're propagating the dynamics of the outbreak, which ultimately impacts everybody from the standpoint of having to wear masks, from the standpoint of the safety of kids in schools, from the standpoint of being able to open up everything the way we were when we were normal," he said.

To address the overall impacts, many officials have been increasing vaccination efforts in under-vaccinated communities.

Ohio Governor Mike DeWine said Sunday his state is seeing "a significant increase" in vaccination rates, particularly in rural areas.

"I think ... fear of the Delta variant is certainly one of the causes," DeWine told CNN's Jake Tapper on "State of the Union."

DeWine said the state is now focusing outreach efforts to the Medicaid population, who he said are "under-vaccinated," through incentives like $100 cash awards for getting the shot.

DeWine said the state's "Vax-a-Million" lottery program also played a major role in reversing a downward trend in vacation rates.

"We think well over 100,000 extra people were vaccinated, at a minimum, because of that," DeWine said. "It was very, very successful. It was something that worked and, you know, we are glad we did it."

DeWine said despite the state's progress on vaccinations, "We have room to grow."

Hospitals overwhelmed with patients

The surge of Covid-19 patients in hospitals could have an impact on others who need medical care, doctors said.

In Austin, Texas, "Our ICU capacity is reaching a critical point where the level of risk to the entire community has significantly increased, and not just to those who are needing treatment for COVID," Austin-Travis County Health Authority Dr. Desmar Walkes said in a statement.

"If we fail to come together as a community now, we jeopardize the lives of loved ones who might need critical care."

In Mississippi, Covid-19 hospitalizations have increased significantly -- including among younger patients, State Health Officer Thomas Dobbs said. All 88 beds in the University of Mississippi Medical Center's intensive care unit had filled up by Friday, according to data from the state's health department.

And in Louisiana, "We're becoming victims of the unvaccinated," said Dr. Christopher Thomas, a critical care physician at Our Lady of the Lake Regional Medical Center in Baton Rouge.

"We currently are overwhelming our bed capacity. We're creating burnout for our teams. And honestly, we're beginning to impact the rest of the health care for the community."

At the Louisiana hospital, 97% of Covid-19 patients in the ICU were unvaccinated, Thomas said. As of Friday, the average age of Covid-19 patients in the ICU was 48.

"That means there are children -- with parents -- who are now in the hospital," he said.