New COVID-19 cases dropped sharply in Evanston today, but the seven-day averages in Suburban Cook County, Chicago and Illinois inched up and remained at very high levels. Statewide, the number of hospitalizations increased for the third day in a row, but they were still about 500 less than one week ago. There were 179 deaths in the last 24 hours.

Continuing to Ramp Up Testing

Even though Illinois will soon be distributing vaccines, Gov. JB Pritzker said today that the State would continue to ramp up its testing as a way to control community spread. “We’re not taking our foot off the gas in our efforts to ramp up testing even further, increasing our ability to identify positive cases quickly, so that we can eliminate community spread and stop further outbreaks in their tracks,” he said.

Dr. Rajiv J. Shah, President of The Rockefeller Foundation, spoke on the importance of testing to open schools and protect workers. He said, “Testing is really the only way out of the false choice between shutting everything down and suffering widespread loss of life.”

Dr. Shah said that Illinois, which is partnering with the Rockefeller Foundation in a testing alliance with 22 other states , has helped “to implement a strategy on testing that makes fast, frequent testing far more accessible and ubiquitous to those who desperately need it to go to school, or to protect themselves doing essential and often frontline healthcare service work.”

As an example, Dr. Shah said the testing program implemented at the University of Illinois at Champaign-Urbana “has demonstrated to America that with fast, frequent and accurate testing, you can actually run educational institutions and keep the testing prevalence rate for students and faculty significantly below the background community rate.

“We at the Rockefeller Foundation have supported dozens of pilot activities around the country in K through 12 education, and some in Universities, all of which validate that insight.

“And it’s why we’ve been part of an effort along with [the University of Illinois] to bring together leaders around the country to use testing as a strategy to more actively reopen K through 12 schools and avoid some of the deep and significant costs in terms of loss of learning and tragic outcomes for children who are forced to be in a learn-at-home environment – often without the resources to be successful.

“It is very clear to us that throughout 2021 and certainly for the first half of next year, if schools are to be open, if healthcare workers are to be safe, if certain essential businesses are to operate in a high background, community spread environment, testing will be more important than ever.

“Using fast frequent testing as a screening tool to enable essential services to go forward remains America’s best strategy to get kids in school, to protect health care workers, and to keep essential workers on their jobs, but on their jobs safely as we get through this very difficult time,” said Dr. Shah.

Extensive testing will not only be important for the reasons advanced by Dr. Shah, but also to measure the effectiveness of the vaccines on controlling community spread throughout 2021.

In the last week, an average of 95,398 COVID-19 tests were administered each day in Illinois, with a test positivity rate of 16.4.

EVANSTON: 10 New COVID-19 Cases Today

There were 10 new confirmed COVID-19 cases of Evanston residents today.

The average number of new cases per day in the last seven days is 24.3. For purposes of comparison, on Oct. 12, the seven-day average was 5.6.

There has been a total of 2,590 COVID-19 cases of Evanston residents during the pandemic, 352 of which are active. An accompanying chart shows the trend. [1]

In the last seven days, there was a total of 174 new COVID-19 cases of Evanstonians. That equates to about 231 new cases per 100,000 people in the seven-day period. The State’s seven-day target is 50 per 100,000.

The test positivity rate over the last seven days is 6.5%. The rate is up from 2.8% on Nov. 1.

No Evanstonian is reported to have died due to COVID-19 in the last nine days. The number of deaths due to COVID-19 remains at 88.

The Impact of NU on Evanston’s Increase in Cases

All Northwestern University (NU) students, staff, and faculty who live in Evanston and who test positive for COVID-19 are included in the case numbers reported above, according to the City. NU students, staff, and faculty who live outside Evanston are not included. [2]

Northwestern University has posted data on its website reporting that between Nov. 30 and Dec. 6, there were 34 new confirmed COVID-19 cases of faculty, staff, and students. The number includes those who live outside of Evanston. The University’s test positivity rate is 1.33. The City claims it does not know how many of these cases are people who live in Evanston. [2]


Several key metrics used by IDPH to measure the spread of COVID-19 are the trend of new cases, the number of new cases per 100,000 population, and the test positivity rate.  Other key metrics are the capacity of hospitals to care for a surge of new patients, and the number of deaths.

First, New Cases.  In Suburban Cook County, there were 1,580 new COVID-19 cases today, and 1,309 in Chicago, for a total of 2,889, up from 2,511 yesterday.

In the State, there were 8,256 new cases reported today.

Statewide, the average number of new cases per day in the last seven days is 9,111. This is down from an all-time high of 12,380 on Nov. 17, and also down from the seven-day average of 9,005 on Dec.2. While the trend has been fluctuating, the number of new cases is still very high.

For purposes of comparison, the average of new cases per day over the seven days ending on May 1 was 2,565, which was the previous high in the spring. The seven-day average today is more than three times that.

Second, New Cases per 100,000 Population. This criterion measures the level of contagion in an area and whether it is at a level that can be contained and suppressed. There are several benchmark numbers. IDPH’s target is that there be fewer than 50 new COVID-19 cases per 100,000 people in a geographic area in a seven-day period. Harvard’s Global Health Institute (HGHI) and the Edmond J. Safra Center say there is “community spread” if cases per 100,000 are between 7 and 63, and that there is “accelerated spread” if they are between 70 and168. [3]

In the seven days ending Dec. 9, the number of new cases per 100,000 people was as follows for the areas indicated:

       Suburban Cook County: 489 (compared to 97 on Oct. 1)

       Chicago: 438 (compared to 86 on Oct. 1)

       Illinois: 503 (compared to 111 on Oct. 1)

The new cases are all at least four times the number for the week ending Oct. 1, and each is at least nine times IDPH’s target.

An accompanying chart shows the trend in the number of new cases during the week ending Dec. 9, compared to the number of new cases for the weeks ending Oct. 1 and Dec. 2. [4]

The chart shows that the number of new cases per 100,000 on Dec. 9 are relatively close to what they were on Dec. 2 for Suburban Cook County, Chicago, and the State. After declining for several weeks, the seven-day trend of new cases is flattening.

Third, a Test Positivity Rate. IDPH’s target is that the test positivity rate be 5% or less, although HGHI and other leading experts say it should be 3% or less.  If a community’s test positivity rate is high, it suggests that the community is not testing enough and not locating people who have milder or asymptomatic cases and who may be spreading the virus. [5]

The most recent seven-day test positivity rates as of Dec. 8 are as follows:

       Suburban Cook County: 12.8%

       Chicago: 12.7%

       Illinois: 11.4%

Each positivity rate is still more than double IDPH’s target, and each is almost four times that of other leading experts. An accompanying chart highlights the rates.

Fourth, Hospital Admissions and Surge Capacity. There were 2,618 hospitalizations due to COVID-19 in Suburban Cook County and Chicago as of Dec. 8, up from 1,456 on Nov. 1. The number of hospitalizations has, however, gone down by about 200 in the last week.

IDPH reported that, as of Dec. 8, Suburban Cook County has a surplus capacity of 19% of medical/surgical beds and 16% of ICU beds; and Chicago has a surplus capacity of 18% of medical/surgical beds and 20% of ICU beds. IDPH’s target is 20% surplus capacity.

On a Statewide basis, the number of hospitalizations due to COVID-19 was 5,284, as of midnight on Dec. 8 This is the third day in a row that hospitalizations have increased. The number is still down from an all-time high of 6,171 on Nov. 23. A chart in the chart box shows the trend.

For purposes of comparison, the highest number of hospitalizations due to COVID-19 in the spring was 4,868 on May 6.

The number of patients using ICU beds is 1,176, up from 347 on Sept. 1. The number of patients on ventilators is 647, up from 142 on Sept. 1.

Deaths: On a Statewide basis, there were 179 deaths due to COVID-19 in the last 24 hours, which brings the total to 13,666.

For the last seven days, the numbers of deaths in the State are 191, 148, 208, 74, 90, 145, and 179 today. The seven-day average is 148. For purposes of comparison, in the spring the highest seven-day average was 118.



1/ Antigen Tests. The Illinois Department of Public Health announced on Oct. 15 that is including both molecular (PCR) and antigen tests in the number of statewide total tests performed in Illinois, and that it is including the positive test results on antigen tests in the confirmed COVID-19 cases reported.  Dr. Ngozi Ezike, Director of IDPH, said on Oct. 30, “You have COVID if you come up with a positive on the antigen test.” The State’s plan is to administer 3 million antigen tests provided by the federal government by the end of this year.

Dr. Michael Mina, Assistant Professor of Epidemiology and Assistant Professor of Immunology and Infectious Diseases at the Harvard T. H. Chan School of Public Health, said an antigen test detects if there is an antigen which is one of the proteins in the virus, while the PCR test looks for the RNA of the virus.

2/ Northwestern University COVID-19 Cases. Ike C. Ogbo, Director of Evanston’s Health & Human Services Department, told the RoundTable that the COVID-19 cases reported by the City include cases of faculty, staff, and students attending Northwestern University who live in Evanston. The RoundTable asked the City in an FOIA Request to provide the number of NU students who tested positive for COVID-19 and who live in Evanston. The City refused to provide the data. On Oct. 26, the RoundTable appealed the City’s decision to the Public Access Counselor of the Attorney General’s Office. On Nov. 13, the City filed a response claiming it does not have any records showing the number of NU students who tested positive for COVID-19 and who live in Evanston.

The RoundTable has asked Northwestern University on two occasions to provide information breaking out the number of new COVID-19 cases of its faculty, staff and students by residency in Evanston. NU did not respond to either request.

3/ Number of Cases per 100,000 Population. On July 1, a network of research, policy and public health experts convened by Harvard’s Global Health Institute and Edmond J. Safra Center published a Key Metrics for COVID Suppression framework that provides guidance to policy makers and the public on how to target and suppress COVID-19 more effectively across the nation. The targets for new COVID-19 cases per 100,000 people are as follows (these are converted from cases per day to cases per week): a) less than 7 cases: “on track for containment;” b) 7 to 63 cases: “community spread,” rigorous test and trace program advised; c) 70 to 168 cases: “accelerated spread,” stay-at-home orders and/or rigorous test and trace programs advised; and d) 169+: ”tipping point,” stay-at-home orders necessary.  The article is available here:

IDPH provides these categories and ratings: 1) “minimal” – fewer than 50 cases per 100,000 in a week; 2) “moderate” – between 50 and 100 cases per week; and 3) “substantial” more than 100 cases per 100,000 in a week.  In its Metrics for School Determination of Community Spread, IDPH says the “target” is 50 cases per week per 100,000 people.

4/ Calculations. The RoundTable calculates the number of cases per 100,000 using case data provided by IDPH and assuming that the population of Suburban Cook County is 2.469 million, that the population of Chicago is 2.710 million, and that the population of Illinois is 12.671 million.

5/ The Test Positivity Rate. On May 26, Johns Hopkins University & Medicine Coronavirus Resource Center said on its website that “the World Health Organization (WHO) advised governments [on May 15] that before reopening, rates of positivity in testing (i.e., out of all tests conducted, how many came back positive for COVID-19) should remain at 5% or lower for at least 14 days.”

Johns Hopkins explains, “The rate of positivity is an important indicator, because it can provide insights into whether a community is conducting enough testing to find cases. If a community’s positivity is high, it suggests that that community may largely be testing the sickest patients and possibly missing milder or asymptomatic cases. A lower positivity may indicate that a community is including in its testing patients with milder or no symptoms.”  Link:

The Harvard Global Health Institute (HGHI) says, “A network of research, policy, and public health organizations convened by Harvard and MIT called the TTSI Collaborative has agreed on a 3% test positive rate or below as a key indicator of progress towards suppression level testing. This targets broad and accessible testing for symptomatic and asymptomatic people. Out of the positive tests that do not come from hotspot testing, at least 80% should come from contact tracing.”

While stating the test positivity target is 5% or less, IDPH provides these categories and ratings: 1) “Minimal” – test positivity rate is equal to or less than 5%: 2) “Moderate” – test positivity rate is between 5% and 8%; and 3) “Substantial” – test positivity rate is over 8%. In its Metrics for School Determination of Community Spread, IDPH says the target is 5%.

Larry Gavin

Larry Gavin was a co-founder of the Evanston RoundTable in 1998 and assisted in its conversion to a non-profit in 2021. He has received many journalism awards for his articles on education, housing and...