Two people infected with COVID-19 spread the virus to more than 30 people during church gatherings in Arkansas in early March, before the first case was ever diagnosed in that state, according to a report from the Centers for Disease Control and Prevention published Tuesday.
The cases illustrate how rapidly the virus can spread to others involved in faith-based organizations, and may have implications for places of worship as churches nationwide figure out how to reopen safely.
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The CDC investigation focuses on an outbreak of COVID-19 at an unnamed church in rural Arkansas. According to the report, two people with symptoms of the virus attended children's events at the church from March 6 to 8.
Neither of those two people, who later tested positive for COVID-19, reported traveling outside of the area, and had no known contact with other confirmed cases.
The pastor of the church, along with his wife, developed similar symptoms a few days later, on March 10 and 11.
But before the pastor started feeling ill on March 11, he attended a Bible study group, unknowingly exposing dozens of people to the virus.
Of 92 people identified to have attended one of the church gatherings from March 6 to March 11, 35 later tested positive, including the pastor and his wife. Three people died.
Two children also tested positive, but did not get very sick.
As soon as the church discovered the infections, in-person activities were canceled and the church was closed, the report said. But widespread transmission within the church and in the community had already occurred.
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Indeed, an additional 26 people living in the community who'd had contact with church attendees also later developed COVID-19. One of those people was sick enough to be hospitalized and died.
It's possible others were infected as well, the CDC report said, but never tested.
"This outbreak highlights the potential for widespread transmission of SARS-CoV-2, the virus that causes COVID-19, both at group gatherings during church events and within the broader community," the researchers wrote in the report.
It's unclear from the report how the virus spread from person to person in these church gatherings. Children's events included collecting offerings by hand from adults, "resulting in brief close contact among nearly all children and attending adults," according to the report.
Singing and buffet meals were also part of the church's events during this time frame.
"These findings underscore the opportunity for faith-based organizations to prevent COVID-19 by following local authorities' guidance and the U.S. Government's Guidelines: Opening Up America Again regarding modification of activities to prevent virus transmission during the COVID-19 pandemic," the authors wrote.
The CDC's guidelines recommend churches consider moving services online, suspending certain traditions such as ritual washing, and finding ways to minimize hand contact between parishioners.