After adding over 1,076,000 new cases throughout the last week, the U.S. now has more than 41.2 million confirmed cases of COVID-19. There have been more than 650,000 COVID-19-related deaths — the highest death toll of any country.

New cases continue to rise at a steady rate. In the past week, there were an average of 49.5 daily new coronavirus cases per 100,000 Americans — essentially unchanged from the week prior, when there were an average of 45.4 daily new coronavirus cases per 100,000 people.

While COVID-19 has spread to nearly every part of the country, cities continue to be the sites of major outbreaks. Experts agree that the virus is more likely to spread in group settings where large numbers of people routinely have close contact with one another, such as colleges, nursing homes, bars, and restaurants. Metropolitan areas with a high degree of connectivity between different neighborhoods and a large population may be particularly at-risk.

The Chicago-Naperville-Elgin, IL-IN-WI, metro area consists of Cook County, DuPage County, Lake County, and 11 other counties. In the past week, there were an average of 24.1 new coronavirus cases every day per 100,000 Chicago residents, less than the national figure. The metro area’s average daily case growth in the most recent week is essentially unchanged from the week prior, when there were an average of 21.4 daily new cases per 100,000 Chicago residents.

The spread of coronavirus depends on a variety of factors and can vary even between neighboring counties. Within the Chicago-Naperville-Elgin metro area, COVID-19 is growing the slowest in Cook County. There were an average of 21.0 new cases per day per 100,000 residents in Cook County during the past week, the least of the 14 counties in Chicago with available data.

Case growth in the Chicago metro area varies widely at the county level. In Jasper County, for example, there were an average of 63.2 new cases per day per 100,000 residents in the past week — the most of any county in Chicago and far more than the case growth rate in Cook County.

While Cook County has the slowest case growth in the Chicago area, it does not have the lowest incidence of cases overall. As of September 16, there were a total of 11,662.8 confirmed cases per 100,000 residents in Cook County, the sixth fewest of the 14 counties in the metro area. For comparison, the U.S. has so far reported 12,697.8 cases per 100,000 Americans nationwide.

In order to slow the spread of COVID-19, city and county governments have ordered the closure of thousands of consumer-facing businesses. These measures have led to widespread job loss and record unemployment. In Cook County, unemployment peaked at 18.1% in April 2020. As of June 2021, the county’s unemployment rate was 10.0%.

To determine the county in every metropolitan area where COVID-19 is growing the slowest, 24/7 Wall St. compiled and reviewed data from state and local health departments. We ranked counties according to the average number of new daily COVID-19 cases per 100,000 residents in the seven days ending September 16. To estimate the incidence of COVID-19 at the metropolitan level, we aggregated data from the county level using boundary definitions from the U.S. Census Bureau. Population data used to adjust case and death totals came from the U.S. Census Bureau’s 2019 American Community Survey and are five-year estimates. Unemployment data is from the Bureau of Labor Statistics and is not seasonally adjusted.

These are all the counties in Illinois where COVID-19 is slowing (and where it’s still getting worse).

Rank in MSA	County	Population	New daily cases per 100,000, week ending September 16	New daily cases per 100,000, week ending September 9	Cumulative cases per 100,000	Cumulative deaths per 100,000
1	Cook County	5,198,275	21.0	18.7	11,662.8	209.6
2	Kane County	531,376	22.5	22.7	12,234.7	157.7
3	McHenry County	307,714	23.5	20.5	10,568.9	101.1
4	DuPage County	929,060	24.0	22.4	11,033.9	145.1
5	Lake County	701,473	24.4	24.1	10,836.8	150.0
6	Porter County	168,636	28.2	24.0	12,557.2	200.4
7	Will County	689,315	28.9	24.1	12,485.7	156.2
8	Lake County	485,707	34.7	28.2	12,799.5	222.6
9	Kendall County	126,054	34.9	30.9	12,008.3	82.5
10	DeKalb County	104,366	36.5	27.3	10,954.7	120.7
11	Kenosha County	168,524	41.4	31.7	12,631.4	204.7
12	Grundy County	50,666	46.8	32.5	13,600.8	159.9
13	Newton County	13,992	48.1	22.3	9,834.2	293.0
14	Jasper County	33,447	63.2	47.3	13,839.8	179.4

Thank you for reading! Have some feedback for us?
Contact the 24/7 Wall St. editorial team.