BELOIT — Rock County COVID-19 cases spiked on Thursday, as businesses reopened and Beloit prepared for its final day of community testing today.

Rock County reported 41 new positive cases on Thursday. The City of Beloit confirmed 30 positive virus cases of the 474 tests completed at Telfer and Krueger parks on May 15.

As of Thursday, 1,782 COVID-19 tests were conducted at Beloit testing sites.

Rock County Public Health Department Public Information officer Kelsey Cordova said Thursday’s increase was “in-part” due to community testing in Beloit and local outbreaks in the county.

Delineated Beloit testing site data will be released either by the city or through the health department, she said.

“We are currently working with the Beloit EOC (Emergency Operations Center) on this,” Cordova added.

Between May 15 and Wednesday, 59 positive cases were reported in Rock County, with Thursday’s increase bringing the county’s total since Beloit testing began to 100 positive cases in the county.

Over 200 cases originate in the Beloit 53511 zip code.

Twenty-six percent of the 157 tests processed on Thursday in Rock County were positive, the largest daily increase since April 26 when 28% of tests were positive. Since May 15, 778 tests were negative and 81 county residents have recovered from the virus, health department data shows.

In the Rock County region, Dane County reported 576 cases and 26 deaths; Green County reported 49 cases and no deaths and Walworth County reported 316 cases and 11 deaths, Wisconsin Department of Health Services (DHS) data from Thursday shows.

The increase in local cases comes as Mercyhealth and SSM Health announced antibody testing availability to patients aimed at learning more about how many people could have been infected.

“We know that some individuals with COVID-19 infection have very mild symptoms or in some cases, no symptoms at all,” said SSM Health Regional President of Medical Groups Mark Thompson. “This test can help us determine if a person was infected at one time, but didn’t know it. These tests give us a better understanding of how many people in a particular area or community have been infected.”

There currently is not enough information available as to whether the existence of antibodies means a person has immunity to COVID-19, or whether they could be re-infected. A positive antibody test should not act as reassurance that patients can stop social distancing, wearing facial coverings or following recommendations from public health, a joint health system news release said.

Beloit Health System is “soon to begin” offering antibody tests, a health system spokesperson confirmed on Thursday.

Across Wisconsin, 472 cases and six additional deaths were reported by DHS on Thursday, bringing the statewide total to 13,885 cases and 487 deaths. To date, 58% of people infected with the virus recovered across the state.

Also on Thursday, Gov. Tony Evers announced a $25 million rental assistance program from federal CARES Act funding.

Across the state line, the Winnebago County Health Department reported 36 new confirmed cases and eight additional virus-related deaths on Thursday, bringing the county total to 1,684 cases and 52 deaths.

In the Winnebago County region, Boone County reported 343 cases and 15 deaths; DeKalb County reported 287 cases and three deaths; McHenry County reported 1,282 cases and 67 deaths; Ogle County reported 178 cases and two deaths; and Stephenson County reported 167 cases and two deaths, data from the Illinois Department of Public Health (IDPH) reported on Wednesday.

In Illinois, IDPH reported 2,268 cases and 87 additional deaths on Thursday, bringing the statewide total to 102,686 cases and 4,607 deaths.