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Staff at long-term care facilities who are the most likely to interact with vulnerable patients are the least likely to have been vaccinated, researchers reported Thursday.

And there is evidence they have been infecting their patients, the US Centers for Disease Control and Prevention-led team reported.

They used data from 300 long-term care facilities across the US. While 75% of physicians working at these facilities had been vaccinated by March of this year, just 46% of aides had been.

“One concern is that nurses and aides in this sample, who have the most patient contact, had the lowest vaccination coverage. COVID-19 outbreaks have occurred in long term care facilities in which residents were highly vaccinated, but transmission occurred through unvaccinated staff members,” Dr. James Lee of the CDC Covid-19 Response Team and colleagues wrote.

Not only are patients at risk – so are the workers themselves. “This finding also has equity implications: national data indicated that aides in nursing homes are disproportionately women and members of racial and ethnic minority groups, with median hourly wages of $13–$15 per hour; aides are also more likely to have underlying conditions that put them at risk for adverse outcomes from COVID-19,” the research team wrote in the CDC’s weekly MMWR report.

“As vaccination was made available on site and lower vaccination rates reflected higher declination rates, vaccine hesitancy might have been an important contributor to undervaccination in these facilities.”

Their findings also indicate disparities in vaccination rates among these workers that correspond to income and other factors.

“Among aides, lower vaccination coverage was observed in those facilities located in more socially vulnerable zip code areas. Together, these data suggest that vaccination disparities among job categories likely mirror social disparities in general as well as disparities in the surrounding communities,” they added.

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“These findings suggest that vaccination promotion and outreach efforts focused on socially vulnerable and marginalized groups and communities could help address inequities,” the team wrote.

It’s possible more workers have been vaccinated since March, the team noted. But such facilities also have high turnover in staffing.

Flu vaccine campaigns have shown that vaccine requirements may be the best way to get the most employees immunized, the team said.