'It Continues To Be A Challenge': The Immunocompromised Seek More Boosters Against COVID-19

CHICAGO (CBS) -- Some people have a harder time fighting COVID-19 than others, including people who are immunocompromised.

CBS 2's Marie Saavedra explains they can get a fourth vaccine starting this week.

"We know a lot of people though who have gotten COVID in the last month."

From his home in Wheaton, Brent Flynn keeps trying to stay healthy. Twenty-six years ago, his brother gave him a kidney. He's been a member of the immunosuppressed community since.

CBS 2 first met Flynn in August, when he shared his hope of getting a third dose, to give his body a better chance at fighting off the virus.

"Because of the compromised immune system that I have, my body may not react to that vaccine and give me 100% protection," Flynn said.

Fast forward to today…

"I did get that," Flynn said. "I got it in August, and that was a full dose of the Moderna vaccine."

Now Flynn and the other estimated seven million American adults who are immunocompromised can get a fourth shot on the books.

"All the protection that I can get, or anyone else who's immunosuppressed, is important," he said.

Back in August, the CDC approved third doses of Pfizer and Moderna for the immunocompromised, considered part of primary immunization. Then in October, the agency said that population could get a booster a fourth shoot of vaccine, six months after their third dose.

Last week, as the Omicron variant raged, the CDC shorted that time to five months. Meaning many could get theirs as early as this week. What about a fourth shot for the rest of us? It's still wait and see, according to CDC Director Rochelle Walensky.

"We will be following our own data carefully as well to see how these boosters are working in terms of waning effectiveness, not just for infection, but importantly for severe disease. So more to come as those data emerge," Walensky said.

In the meantime, Flynn's plans for his fourth shot in February could get moved up. And he's appreciative.

"It continues to be a challenge for everybody, you know," Flynn said.

A good amount of the information the CDC is using to make these decisions about the immunocompromised and shortening timeframes between shots is coming from Israel.

That country is already offering fourth doses to high risk groups and older adults. The CDC director said they're closely watching that data.