Members of the Wisconsin National Guard medical team help with free COVID-19 drive-thru testing Monday at Dawson Ball Fields in Janesville. Monday was the first day of a five-day run of testing at the site, which is south of downtown.

The number of active and confirmed cases of COVID-19 in Rock County hit 1,030 on Thursday, a 66% increase from two weeks ago.

The county saw 96 new COVID-19 cases Thursday, bringing the total to 3,634, according to data from the Rock County Public Health Department.

Of cases reported Thursday, 91% were positive, the highest single-day positivity rate so far in the county.

The health department in a Facebook post Thursday afternoon said negative test results are not being reported to the health department as quickly as positive results, therefore skewing local positivity rates.

Negative results have been pushed bask as less of a priority as health departments across the state become overwhelmed with increased COVID-19 activity, according to the post.

Individuals with negative results are receiving those results quickly, before the health department gets them, the post says.

Positivity rate data will likely be skewed until Tuesday, according to the post.

Epidemiologist Nick Zupan said Wednesday that any positivity rate above 10% is “concerning.”

Hospitalizations for COVID-19 decreased from 30 on Monday to 20 on Thursday, according to the data.

Of all Rock County COVID-19 cases, 7% have been hospitalized.

No new deaths were reported. Since March, 37 Rock County residents have died from COVID-19.

Zupan said Wednesday the disease is spreading through gathering places, parties, family get-togethers, weddings and other social events more quickly than in schools.

School-age children are being infected significantly more frequently than in the first five months of the pandemic.

Young adults ages 15 to 24 make up 20% of the county’s cases, but Zupan said other age groups are starting to see more positive cases and are closing the demographic gap.

This story was updated at 11 a.m. Oct. 16 to reflect a statement made by the health department in a Facebook post regarding positivity rates.