CHICAGO (CBS) — We first told you about Alan Matthews – a longtime resident of the Landmark Nursing Home in Richton Park – two weeks ago.

His cousin came to us after finding out he was months overdue for his second COVID-19 vaccine dose. And CBS 2 Political Investigator Dana Kozlov found Matthews is likely not the only one – because no one is really keeping track.

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“I don’t know if they dropped the ball or they’re just negligent,” Matthews’ cousin, Cheryl Bellamy-Bonner, said in our report on Tuesday, June 13. “I don’t know if he’s the only patient, or one of many patients that haven’t gotten their second shot.”

That was Bellamy-Bonner’s concern after a letter came in from the Illinois Department of Public Health flagged her that Matthews had only gotten one COVID vaccine shot.

It made Kozlov wonder how many more people might be in Matthews’ very situation.

“I believe that your case is probably not an isolated case,” said infectious disease specialist Dr. Alexander Stemer.

Stemer is the medical director for a group of Symphony nursing homes in Indiana. He said one problem is nursing homes do not have access to new patients’ vaccination data.

But we found no one is tracking nursing home vaccinations either. The nursing homes are expected to do it themselves – by providing that information to the Centers for Disease Control and Prevention every week.

According to the CDC website, 31 percent – almost a third – of Illinois nursing homes are not doing that.

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“I can’t speak to why some of these facilities don’t have it up now,” said Chicago Department of Public Health Director Dr. Ngozi Ezike.

Ezike stopped short of criticizing the noncompliant facilities, but added that the IDPH will soon launch a link listing vaccination rates by specific homes.

“So that, you know, if the vaccination rate looks a little bit low, you know, you can double-check – did my loved one get both vaccines?” she said.

“It eats away at me,” said the AARP’s Al Hollenbech. “We can do better.”

Hollenbech said the Delta variant raises the stakes even more for such vulnerable residents – adding the low staff vaccination rates and flatlined vaccinations across the board only add to the threat.

“In terms of who’s responsible for that, it’s the county health departments and the state department of health,” Hollenbech said.

“The question is, can you mandate vaccines?” added Stemer.

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That conversation is growing. More than 1,000 federal VA health care workers now need to be vaccinated, and private health care systems are also now mandating them. Gov. JB Pritzker said he is reviewing options.