The latest surge of coronavirus cases powered by the omicron variant has caused extremely high numbers of employees to miss work because of illness, exacerbating the country’s persistent labor shortages and threatening to complicate the labor market’s push toward pre-pandemic employment levels.

Between Dec. 29 and Jan. 10, approximately 8.8 million workers reported not working because they were sick with the coronavirus or caring for someone who was, according to data from the Census Bureau.

Those numbers are nearly triple the levels from the first two weeks of December, before cases had started to peak around the country. They were also the highest numbers since the agency started taking the survey in April 2020 — well over last January’s peak of 6.6 million workers out.