The CDC on Thursday shortened the recommended isolation time for health care workers who test positive for COVID-19 from 10 days to seven days if they're asymptomatic.

Driving the news: The new guidance follows calls by health officials for the CDC to shorten its recommendation on isolation for fully vaccinated people who test positive due to concerns about the Omicron variant.

• Some health experts have warned that hospitals will face even more severe shortages of staff due to Omicron, per Axios' Bob Herman.
• The guidance also says fully vaccinated health care workers who've received booster shots don't need to quarantine at home after high-risk exposures.

What they're saying: "As the healthcare community prepares for an anticipated surge in patients due to Omicron, CDC is updating our recommendations to reflect what we know about infection and exposure in the context of vaccination and booster doses, CDC director Rochelle Walensky said in a statement.

• "Our goal is to keep healthcare personnel and patients safe, and to address and prevent undue burden on our healthcare facilities," Walensky added.

Yes, but: The National Nurses United, the largest union of registered nurses, condemned the CDC's actions, warning in a statement that "no longer requiring fully vaccinated and boosted health care workers to quarantine after a high-risk exposure ignores basic tenets of infection control and the precautionary principle."

• The union also sent Walensky a letter saying, "Weakening Covid-19 guidance now, in the face of what could be the most devastating Covid-19 surge yet, will only result in further transmission, illness, and death."