As officials continue to push preventive measures, such as wearing masks and practicing social distancing to keep infection rates low, they also have been vocal in warning against large gatherings.
But Americans have continued to congregate, leading to outbreaks tied to a number of events, from Memorial Day and Fourth of July celebrations to a massive motorcycle rally in Sturgis, South Dakota.
The wedding held in Millinocket on August 7 had about 65 guests, in violation of the state's 50-person cap for indoor events, Maine CDC said.
The event is linked to outbreaks that have unfolded at a nursing home and a jail, both more than 100 miles away from the wedding venue, and among people who had only secondary or tertiary contact with an attendee.
Residents at Maplecrest Rehabilitation and Living Center accounted for 39 cases tied to the wedding and six of the seven deaths thus far, Maine CDC Director Dr. Nirav D. Shah said.
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"The virus favors gatherings," Shah added. "It does not distinguish between happy events like a wedding celebration, or sad farewells, like a funeral."
Despite such somber warnings, about 1,500 people descended on a New Jersey boardwalk house featured in MTV's "Jersey Shore" Monday night, ending in eight arrests, according to Seaside Heights police.
The event was organized by a group of YouTube pranksters, according to Seaside Heights Police Detective Steve Korman, and officials say they are now worried about how they will track possible infections among more than a thousand people.
Universities try to get ahead of outbreaks
Outbreaks have been cropping up at colleges and universities, bedeviling administrators working to contain spread.
More than 50,000 coronavirus cases have been reported at colleges and universities in all 50 states.
Citing a significant rise in cases among students, Colorado University of Boulder will be moving to a 14-day quarantine period for students living within the city, according to its website.
The University of Arizona is taking a similar tact, urging students to shelter in place until the end of the month after a large number of positive cases. The university reported 261 positive cases on Monday, according to the school's coronavirus dashboard.
Two students were expelled and three suspended at the University of Missouri for violating rules that require students who test positive to isolate and comply with social distancing.
"These students willfully put others at risk, and that is never acceptable. We will not let the actions of a few take away the opportunity for in-person learning that more than 8,000 faculty and staff have worked so hard to accomplish for the more than 30,000 MU students," the university said in a statement Tuesday.
Coronavirus could have been in the US as early as December
Though outbreaks attributed to coronavirus were not widely documented until the spring, the virus may have circulated in the United States as early as December, about a month earlier than believed by the US Centers for Disease Control and Prevention, according to researchers with UCLA.
A study, published last Thursday in the Journal of Medical Internet Research, found a statistically significant increase in clinic and hospital visits by patients who reported respiratory illnesses as early as the week of December 22.
The first known case of Covid-19 in the US was thought to be a patient in Washington who had visited Wuhan, China, according to the CDC. The case was reported in January.
But the number of patient visits to the ER for respiratory complaints, as well as the number of people hospitalized with acute respiratory failure between December 2019 and February 2020, were all up, compared to records from the past five years. Though the cases could have been from the flu, the numbers are notable, Dr. Joann Elmore told CNN.
Dr. Claudia Hoyen, an infectious disease specialist at University Hospitals Cleveland Medical Center who did not work on the study, said she believes it's possible Covid-19 may have been in the US much sooner than first realized.
But Kristian Andersen, a professor of immunology and microbiology at Scripps Research, disagreed.
"We know from the SARS-CoV-2 genetic data that the pandemic started in late November / early December in China so there's absolutely no way the virus could have been spreading widely in December 2019. From the same genetic data we know that widespread transmission didn't start in the United States until (around) February 2020," Andersen said in an email.
"The paper is picking up spurious signals and the hospitalizations are more likely from flu or other respiratory diseases," Andersen wrote.
Returning to normal is a long way off
Some officials are preparing for the coronavirus-altered way of life to continue for a while longer.
Boston will allow restaurants to continue using private outdoor and public street and sidewalk spaces to serve customers through December 1, Mayor Marty Walsh announced Tuesday. The practice was supposed to last until October 31.
"We're trying to help our restaurants continues to take advantage of outdoor space as long as possible," Walsh said.
And though researchers are racing to have a vaccine ready in the new year, Dr. Soumya Swaminathan, chief science officer at the World Health Organization in Geneva, said Tuesday that the world might not be able to begin thinking about returning to "pre-Covid" life until 2022.
Swaminathan, speaking to journalists during a virtual meeting hosted by the United Nations Foundation, said 60% to 70% of the global population would need to have immunity before there is a dramatic reduction in transmission of the virus.
"We're looking at 2022 at least before enough people start getting the vaccine to build immunity," said Swaminathan. "So, for a long time to come, we have to maintain the same kind of measures that are currently being put in place with physical distancing, the masking and respiratory hygiene."