Lewiston High School nurse Melissa Gendron, middle right, checks the license plate of a vehicle as St. Mary's Health System nurse practitioner, Carolyn McNamara, takes a swab from a staff member at a coronavirus testing site, Tuesday, Jan. 12, 2021 at Lewiston Middle School in Lewiston, Maine. Credit: Russ Dillingham / Sun Journal via AP

After maintaining one of the lowest rates of coronavirus transmission in the U.S. since the pandemic hit 10 months ago, Maine’s rate of new virus infections exceeded a dozen other states this past week and lowering case levels may only get more difficult.

Maine saw a record 823 new virus cases reported on Friday, the third straight day with infections topping 800. The seven-day average of new cases sits at 627, up more than 50 percent compared to a month ago. The 64 deaths recorded in the first two weeks of January already make it the third most deadly month of the pandemic.

Total cases and deaths since the start of the pandemic still remain among the lowest in the country. But 12 states and the District of Columbia saw fewer new cases on a population-adjusted basis than Maine did last week, according to the New York Times, and the nature of the virus’ spread means that current levels could worsen as most Mainers remain unlikely to be vaccinated for several more months.

Cases have been climbing in Maine since mid-October, with daily infections surpassing 100 for the first time at the end of that month. While most counties have seen flare-ups at different points in the past few months, spread has occurred in urban areas and small towns.

New infections have been spread fairly evenly across age groups, with outbreaks in long-term care facilities, workplaces and schools. Gov. Janet Mills tightened the state’s mask mandate in response to increased cases in December, but has declined to implement new business or social restrictions as the virus has surged. Maine’s restrictions are mostly in line with other New England states, though some states have stricter gathering limits.

The record number of cases this week comes after state health officials predicted a post-holiday spike due to potential transmission from increased travel as well as more testing when people returned from travels. Maine has tested for the virus more this month after a drop over the holidays, with more than 82,000 tests performed for the week ending Friday, roughly double the level the state was performing in October.

But the increase in cases likely reflects spread of the virus rather than testing alone, as the test positivity rate has remained high, with the seven-day average sitting at 5.6 percent as of Friday after dipping below 1 percent in the fall and not surpassing 5 percent until late December. Nirav Shah, director of the Maine Center of Disease Control and Prevention, reiterated Friday that holiday gatherings were a likely driver of transmission.

Reining in that holiday spread could be difficult, as the higher case rate makes mitigation strategies successful for Maine earlier in the pandemic less effective now, said Robert Horsburgh, an epidemiology professor at Boston University.

“When people went out six months ago, there was very little chance they would run into somebody who had it, and now there’s a pretty good chance because there are a lot more people out there who have it,” Horsburgh said. “And so the problem is, once it starts to increase like that, it’s very hard to tamp it back down.”

The Maine surge comes amid a nationwide increase as well as new concerns that the virus could explode even further due to the spread of two more transmissible strains. One of those variants, which originated in the United Kingdom, was confirmed to be in Connecticut last week.

Neither strain has been detected in Maine so far, though Shah said Friday that the spread of either was a possibility, as not all positive samples of the virus in Maine are sent to labs to be tested for the new strain.

The states that saw fewer new cases of the virus than Maine over the last week include those that had maintained comparatively low case counts throughout the pandemic, such as Vermont, Hawaii and Oregon, as well as some that saw among the worst outbreaks in the fall but have since brought down case levels, such as North Dakota, where 12.5 percent of the population has had the virus at some point.

Maine still maintains the third-lowest case level in the U.S. since the start of the pandemic on a population-adjusted basis, with only Hawaii and Vermont performing better. Only those states and Alaska have seen fewer per-capita deaths than Maine.

“There probably wasn’t much infection in Maine in the first place, so it takes a long time for things to start going,” Horsburgh said. “But once it gets going, it really shows up.”

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