Alabama is seeing a significant rise in COVID-19 cases as the extremely contagious omicron variant of the coronavirus continues to sweep the nation.

Fifty-two of the state’s 67 counties are now showing high levels of community transmission, according to the Alabama Department of Public Health. During the last week, 18.2% of COVID-19 tests in the state have come back as positive.

The seven-day rolling average of daily new cases in Alabama has nearly tripled over the past two weeks, rising from 540 new cases per day on Dec. 11 to 1,586 new cases per day on Dec. 25, according to researchers at Johns Hopkins University.

There were 528 COVID-19 patients in state hospitals on Monday. That is up by nearly 200 over the last two weeks, but lower than during the previous two pandemic peaks, when there were as many as 3,000 COVID-19 patients in state hospitals, and the state was seeing more than 4,000 new cases reported each day.

State health officials on Dec. 16 said Alabama had confirmed its first case of the swift-moving omicron variant of the coronavirus.

Dr. Jeanne Marrazzo, director of infectious diseases at the University of Alabama at Birmingham, last week said places with low vaccination rates will be faced with “crushing demand on the health care system” as omicron spreads, even if it isn’t as deadly as earlier versions of the virus.