Nurse Cassandra Pateneaude treats a patient in the hallway of the Maine Medical Center emergency department on Dec. 8, 2021. Credit: Courtesy of MaineHealth

AUGUSTA, Maine – Maine recommended providers no longer use two types of COVID-19 treatments found to be ineffective against the omicron variant as the highly contagious strain is now accounting for at least 70 percent of new infections here.

The Friday notice from the Maine Center for Disease Control and Prevention was the agency’s firmest acknowledgment that omicron is now dominant, with the agency telling health care providers that one of three federally authorized monoclonal antibody treatments, sotrovimab, should be used because it is the only one effective against the super-contagious strain.

The decision highlights the challenges that the omicron variant poses for the state’s stressed health care system, as the highly contagious strain spreads rapidly. While it leads to more mild cases on average, more transmission could cause serious cases to rise, as evidenced by the record 403 patients hospitalized with the virus on Monday.

Data on the prevalence of variants is imprecise as only a fraction of positive COVID-19 tests are genetically sequenced. There are also delays in reporting of variants as genetically analyzing each positive sample takes time.

But there is little doubt the omicron variant has been behind the recent surge in cases across the U.S. The prevalence of the variant nationwide increased from an estimated 38 percent of U.S. cases in mid-December to 95 percent by the end of the month, according to analysis by the U.S. Centers for Disease Control and Prevention. That coincided with a more than fivefold increase in cases over the past month, according to the New York Times.

However, the omicron variant occupied a smaller share of cases in New England than the rest of the U.S. as of late December, albeit still a majority, the U.S. CDC analysis found. That fits with Maine’s data showing the more contagious strain got off to a later start here.

Officially, the omicron strain accounted for just shy of 9 percent of virus samples tested for variants in Maine in late December. But estimates from Maine laboratories suggest it now accounts for between 70 percent and 90 percent of new cases here, according to the Maine CDC memo to health care providers.

Despite the lag in data, the high number of cases in the past week among almost entirely vaccinated hospital workers has Steven Michaud, the president of the Maine Hospital Association, convinced that the new strain is beginning to dominate case counts in Maine, saying the virus is “all around us” in ways that it has not been before.

“There is no way that this is not predominantly omicron going through the state very rapidly,” he said.

Sotrovimab is now in short supply both in Maine and across the country. The treatments are given as infusions to older and high-risk people who have either tested positive for COVID-19 or been exposed to the virus.

BDN writer Michael Shepherd contributed to this report.

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