The highly contagious Omicron variant is affecting essential retailers Walgreens’ (WBA) and CVS’ (CVS) staff to the point that the companies have been forced to temporarily close certain locations due to a shortage of workers.

CVS told Reuters that stores affected by the closure will shut down on one or both days of the weekend as a temporary response to the continuous spread of the Omicron variant that has caused a nationwide staffing shortage.

According to the Centers for Disease Control and Prevention, the Omicron variant accounts for 98% of all COVID-19 cases.

In a statement to the news outlet, CVS said, “The adjusted operating hours in these stores are temporary.”

According to The Wall Street Journal, Walgreens is also challenged with workers who have been impacted by the Omicron variant and has closed some stores on the weekend across the U.S.

A spokeswoman for the drugstore retailer told the Journal that the vast majority of the chain’s 9,000 U.S. stores are open their regular hours.

She added, “The ongoing labor shortage, combined with the surge of COVID-19 cases, has resulted in isolated instances in which we’ve had to adjust operating hours or temporarily close a limited number of stores.”

The temporary closures are a departure from earlier in the pandemic when Walgreens and CVS scrambled to hire thousands of workers nationwide to meet the demand from consumers as an essential business.

Walgreens and CVS are not the only retail chains that are affected by Omicron and have had to modify their hours.

Both Macy’s and Walmart have announced reduced hours at locations or temporarily closed stores due to worker shortages because of virus infections. Media reports have indicated that Walmart has closed a steady stream of stores throughout the U.S. for cleaning and sanitation because of COVID-19.

Rite Aid announced in December that it would close its stores an hour earlier, and provide walk-in COVID vaccines for only one hour a day due to employee limitations, the Journal said.

As of Friday at 11:57 a.m. EST, shares of Walgreens were trading at $53.82, down 68 cents, or $0.37%, while shares of CVS were trading at $105.57, up 23 cents, or 0.22%.

Following CVS Caremark’s announcement that it will go smoke-free, health-conscious consumers want Walgreens Co. to follow. Reuters