Originally Published: 23 JUL 21 09:42 ET

Updated: 23 JUL 21 12:50 ET

By Miguel Marquez, Carolyn Sung and Travis Caldwell, CNN

(CNN) -- Christy Henry had played it safe during the pandemic.

Wearing a mask in public and rarely coming into contact with others, the 56-year-old former nurse, who now works as a nursing instructor, resides in southern Missouri with her retired husband and children.

However, after Covid-19 vaccines became widely distributed in the spring, Henry and her family chose to not get inoculated. Henry said they felt because of their rural location and lifestyle, their risk of exposure was low.

But then she began to feel unwell about three weeks ago. "Never in a million years do you think it's going to happen to you," she said.

Her family did not have any Fourth of July gatherings and she is not sure how they got infected. But now, she and her husband, Lonnie, are in the hospital recovering from Covid-19.

While one of her six children also tested positive and avoided hospitalization, Lonnie is currently on a ventilator. Christy herself was intubated for at least two days.

Her doctor told her she is lucky to be alive, Christy told CNN from her hospital bed.

"Covid-19 is extremely, extremely serious," she said, urging everyone she knows to get vaccinated.

Henry is one of many dealing with Covid-19 amid a summer surge that has again strained hospital resources.

The difference in prognoses between those vaccinated and those who are not is also growing apparent. More than 97% of people who are entering hospitals for Covid-19 treatment are unvaccinated, CDC Director Dr. Rochelle Walensky said at a White House briefing last week.

"There is a clear message that is coming through. This is becoming a pandemic of the unvaccinated," Walensky said.

Driven in large part by the Delta variant that is believed to be more transmissible and dangerous, 48 states are showing a seven-day average of new cases at least 10% higher than the week before, according to data from Johns Hopkins University.

Dr. Howard Jarvis, an emergency medical physician in Springfield, Missouri, noted that the Delta variant's infection rates are being seen readily in area hospitals.

"I think this variant is just more severe than what we were experiencing previously," he said.

Getting ahead of the surge in Missouri

Roughly 40% of Missouri residents are fully vaccinated, according to the state Department of Health and Senior Services, a number that trails the national average of nearly 49%. Covid-19 cases within the state have risen about 18% in the last two weeks, and hospitalizations are up sharply since May.

As the number of cases tick higher, nurses and doctors once again find themselves on the frontline of the pandemic.

Kate Giacchi, a critical care nurse at the University of Missouri Hospital, said that staff are "mentally and physically and emotionally worn out" from dealing with Covid-19 for more than a year, with no relief in sight.

"The disease is real and it's killing people and it is preventable," she said.

As health care workers are at greater risk of contracting Covid-19 as more patients arrive, some facilities are requiring all employees receive Covid-19 vaccinations. The Mercy Health system in Missouri and neighboring states has set a deadline of the end of September for employee vaccinations.

"We've got a narrow window to basically sustain or get ahead of where we are right now," said Craig McCoy, president of Mercy Springfield Communities.

"As of this morning, we've got 172 people hospitalized which is our all-time peak," he told CNN.

Susan Dean, a retired health care worker in Missouri, is like those in the industry who are vaccine-hesitant. She told CNN she is wary of the long-term effects the vaccine may have, and did not agree with mandates at hospitals like those administered by Mercy that all health care staff be vaccinated.

"I don't think we know enough about the vaccine to say, 'This is what it does,'" she said.

Despite the efficacy of the vaccines that have been proven in clinical trials as well as real-world data, vaccination rates in Missouri and nationwide are lagging from spring highs, and officials are encouraging unvaccinated Missourians to receive their doses as quickly as possible.

"While the Delta strain is more contagious, the vaccine has been proven to be safe and effective against it," Gov. Mike Parson said on Wednesday. "We encourage all Missourians to consider getting vaccinated as almost all new Covid hospitalizations can be attributed to unvaccinated individuals.

"We understand that some Missourians are on the fence as to whether to get vaccinated or not, and that is a big decision for many families," he said. "That is why we encourage you to engage in conversation with your personal doctor, your local health care officials or other trusted community leaders so that you can get the facts and decide when getting vaccinated is right for you."

Christy Henry, who asks for continued prayers for the health of her husband, agrees.

"I'm going to tell everybody, everybody I know and I love," she said, "that you need to get vaccinated."