This article has been revised to reflect the following: TenHaken says the explanation he offered of herd immunity isn’t part of the city’s strategy to manage COVID-19 in Sioux Falls. The definition of low incident plateau has also been updated.

SIOUX FALLS, S.D. (KELO) — With active case numbers in the Sioux Falls area back at levels not seen since the end of May, the city’s mayor said he’s “fairly comfortable” with the case count at a Monday morning news conference on the coronavirus pandemic.

“The more people who get COVID, just to be blunt, the closer we move towards herd. The more people who get it without the getting the severe effects of needing hospitalization, the closer we get to less spread in our community, because more people will have had it,” TenHaken said.

While the percent positive rates in the Sioux Falls area have been increasing since late July and the weekly rate was 12% as of Aug. 17, TenHaken said there has not been a corresponding increase in hospitalization rates.

On Aug. 4, 25 people were hospitalized and on Aug, 17, 33 people were hospitalized. Since July 19, the lowest hospitalization day was 21 on July 31, according to the city’s COVID-19 dashboard.

City of Sioux Falls COVID-19 hospitalization numbers. City of Sioux Falls chart.

The percent positive is the number of positive COVID-19 cases in relation to the number of people tested.

TenHaken said when all COVID-19 data is considered, the city does not need a mask mandate.

Data from the Centers for Disease Control (CDC) and other health organizations shows that most people who got COVID-19 have not been hospitalized and a low number of people who need hospitalization have not needed intensive care units.

But some COVID-19 patients who could be at risk for hospitalization are being monitored and treated at home, said Dr. Mike Wilde of Sanford Health.

“It certainly has decreased the need for hospitalization,” Wilde said of home monitoring. Wilde said he did not specifically know how home monitoring of COVID-19 has impacted the hospitalization rates.

The World Health Organization, the Centers for Disease Control and other health care experts use the percent positive rates as way to indicate the control of the transmission of COVID-19 in areas. The WHO has recommended that communities do not re-open unless they have a 5% percentage positive rate for 14 days. The organizations also say hospitalization rates are an important part of COVID-19 planning and response.

The Sioux Falls area has 194 COVID-19 cases per 100,000, 528 cases over 14-days and 503 active cases as of Aug. 17.

Sioux Falls area COVID-19 statistics. Data is a Sioux Falls COVID-19 dashboard chart.

The city of Sioux Falls includes this CDC definition of a low incident plateau on its dashboard: “Note regarding the 14-day total, according to the CDC, “A low-incidence plateau is defined as a very low number of new cases reported (below 10 cases per 100,000 population over 2 weeks) with only minimal change in daily cases.”  “This equates to less than 26 cases over the course of 14 days for the Sioux Falls Area,” according to the dashboard.

The CDC and others watch the percent positive rate in part because there is an accurate assumption that there is a corresponding rate for hospitalizations, TenHaken said. “We haven’t seen that here yet,” he said.

In response to a follow-up question after the news conference ended, Dr. Mike Elliot of Avera Health, said the percentage positive rate is important but it is one of several information factors used to monitor COVID-19. “If you are only testing symptomatic people, then your (percent) positive rate goes up,” Elliot said.

Some people who are asymptomatic are being tested in the Sioux Falls area, Elliot said.

TenHaken said a mask mandate is a card that could be played in the future if needed.

As to what would cause the city to play the mask card, TenHaken said a climbing percent positive COVID-19 rate combined with a climbing hospitalization rate would be a reason to consider it.

“One number we’re watching…is that 40 hospitalization threshold,” Ten Haken said. If Sanford and Avera each had 40 hospitalizations that would be a key factor in considering any COVID-19 restrictions. “That kind of enters us into another threshold…,” he said.

Yet, he said, it’s hard for him to envision any return to restrictions at businesses or gatherings that happened early in the pandemic.

The Mayor and the two doctors all said they expected COVID-19 cases to increase when school starts.

TenHaken pointed out the news conference was being held on a day when some private schools in the city were returning to class.

Public schools are scheduled to start in person instruction on Aug. 27.

If schools are to remain open, the public has a role in reducing COVID-19 transmission, TenHaken said.

“…it’s so important to stay vigilant,” Elliot said. COVID-19 is serious, he said.

Elliot and Wilde encouraged people to practice good hygeine, practice social distancing and wear masks.

Wilde said it is known that the coronavirus can be transmitted between people in close proximity and on common surfaces such as door handles.

Monday’s news conference was the first COVID-19 related news conference since May 27th.