MADISON – One boy who arrived at a southeastern Wisconsin summer camp unknowingly infected with COVID-19 likely spread the virus to 116 people, a new report by the Centers for Disease Control and Prevention shows.
Between July 2 and Aug. 11, one infected camper who had tested negative before arriving led to COVID-19 diagnoses for nearly 80% of the camp’s attendees, according to the report that was released Thursday.
On July 28, state health officials tested nearly all attendees at a faith-based camp for boys after a small group of children who were in close contact with the boy became sick or tested positive. At least one confirmed case was found in every dormitory room and yurt over the course of the outbreak, the report said.
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The CDC did not identify the camp but described it as a boys’ overnight summer school retreat that included 152 high school-aged boys, counselors, and staff members from 21 states and territories and two foreign countries.
All illnesses were mild to moderate, and no hospitalizations or deaths occurred, the CDC said.
Julie Willems Van Dijk, deputy health services secretary, said she did not know the details of the investigation her department conducted but said the outbreak’s size did not surprise her.
“COVID-19 spreads like wildfire when you bring a lot of people together in a relatively small space,” she said. “If there was one person who was ill with COVID-19, they easily spread that to everyone in their housing unit and then the nature of summer camp where you eat meals together, go swimming together, do activities together, sing around the campfire together — all of those activities are great spreading events.
“That’s how it would go to one person to over 100 people in a very short period of time,” she said.
According to the report, students traveled to the camp on July 2 by airplane and ground transportation to “a regional hub” where they met with counselors and staff members and boarded three buses to the retreat.
The next day, one camper who had received a negative test less than a week earlier began to experience a sore throat, a cough and chills. He tested positive for the virus two days later.
The camper later learned that a family member received a positive test result about a week after he arrived.
He was isolated in a private room and 11 of his close contacts, which included four roommates, were quarantined together in a dorm. Those 11 contacts received negative results from a rapid antigen test, which have lower reliability rates than regular COVID-19 tests, and were released from quarantine on July 7. The test results were not confirmed by public health officials.
Between July 4 and July 7, six of the 11 close contacts of the first patient and 18 additional students with unknown exposure histories reported mild symptoms, according to the report.
These students were given masks, but contact tracing was not done and the students were not isolated.
On July 13, a second student who was one of 11 close contacts tested positive at a local health clinic, which prompted state health officials to be notified of an outbreak.
On July 28 and in early August, the state health services department coordinated testing for the vast majority of the 152 camp attendees. At the time, no new illnesses had been reported since July 20.