The seven-day averages of new COVID-19 cases have stayed relatively flat or declined for 14 days in Suburban Cook County, Chicago and the State, and for 10 days in Evanston, although at very high levels. The number of hospitalizations in the State declined for the fourth day in a row.
Time will tell whether the numbers were lower today due to the holiday, and whether they will bounce back up due to the travel and gatherings for Thanksgiving as health experts fear.
EVANSTON: 16 New COVID-19 Cases Today
There were 16 new confirmed COVID-19 cases of Evanston residents today, and 23 yesterday. The average number of new cases per day in the last seven days is 29.3. For purposes of comparison, on Oct. 12, the seven-day average was 5.6.
There has been a total of 2,274 COVID-19 cases of Evanston residents during the pandemic, 394 of which are active. An accompanying chart shows the trend. 
In the last 7 days, there were a total of 205 new COVID-19 cases of Evanstonians. That equates to about 277 new cases per 100,000 people in the 7-day period. The State’s 7-day target is 50 per 100,000.
The test positivity rate over the last 7 days is 5.3%. The rate is up from 2.8% on Nov. 1.
One Evanstonian died due to COVID-19 in the last 48 hours, bringing the total number of deaths to 85.
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. If NU students, staff or faculty live outside Evanston, they are not included. 
Northwestern University has posted data on its website reporting that between Nov. 19 and Nov. 25 there were 62 new confirmed COVID-19 cases of students, staff and faculty, which includes those who live outside of Evanston. Between Nov. 20 and 26, NU says there were 50 cases. The City claims it does not know how many of these cases are people who live in Evanston. .
SUBURBAN COOK COUNTY, CHICAGO AND ILLINOIS
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. Another key metric is the number of hospitalizations due to COVID-19 and hospitals’ capacity to care for a surge of new patients.
First, New Cases. In Suburban Cook County, there were 1,263 new COVID-19 cases today, and in Chicago there 1,478, for a total of 2,741.
In the State there were 7,574 new cases reported today, the lowest number since Nov. 4. The average of new cases per day in the last seven days is 10,236.
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 for the State, until the increases in the last month. The 7-day average today is about four times that.
The trends of new cases in Suburban Cook County, Chicago and the State are shown in accompanying charts. One significant point is that the 7-day average of new cases for each of these public bodies is lower today that it was one week ago.
The trend is generally flat or declining, although the number of new cases remains very high.
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. IDPH’s target is that there be fewer than 50 new COVID-19 cases per 100,000 people in a geographic area in a 7-day period. Harvard’s Global Health Institute (HGHI) and the Edmond J. Safra Center say that a stay-at-home order is necessary when the weekly cases exceed 169. 
In the 7-days ending Nov. 27, the number of new cases per 100,000 people were as follows for the areas indicated:
- Suburban Cook County: 516 (compared to 97 on Oct. 1 )
- Chicago: 495 (compared to 86 on Oct. 1)
- Illinois: 566 (compared to 111 on Oct. 1)The new cases are five times the number for the week ending Oct. 1, and each is about ten times IDPH’s target. They are about three times the number that HGHI says necessitates a stay-at-home order.An accompanying chart shows the trend in the number of new cases during the week ending Nov. 27, compared to the number of new cases for the weeks ending Oct. 1 and Nov. 20. 
Importantly, the chart shows that while the number of new cases per 100,000 is still very high, the number of new cases per 100,000 on Nov. 27 is lower than the number on Nov. 20 for Suburban Cook County, Chicago, and the State. The trend of new cases is declining.
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. 
The most recent 7-day test positivity rates are as follows:
- Suburban Cook County: 13.3% (as of Nov. 26)
- Chicago: 12.4% (as of Nov. 26)
- Illinois: 12.2% (as of Nov. 27)
Each positivity rate has declined at least 2.5% in the last 10 days. But each is still more than double IDPH’s target and four times that of other leading experts. An accompanying chart highlights the rates.
Fourth, Hospital Admissions and Surge Capacity. There 2,901 hospitalizations due to COVID-19 in Suburban Cook County and Chicago as of Nov. 26, up from 1,456 on Nov. 1.
IDPH reported that as of Nov. 27, Suburban Cook County has a surplus capacity of 22% of medical/surgical beds and 21% of ICU beds; and Chicago has a surplus capacity of 22% of medical/surgical beds and 19% of ICU beds. IDPH’s target is 20% surplus capacity.
On a Statewide basis, the number of hospitalizations due to COVID-19 was 5,829, as of midnight on Nov. 26, and it is the fourth decline in four days. 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 1,215, up from 347 on Sept. 1. Patients on ventilators is 698, up from 142 on Sept. 1.
If additional hospital beds are needed in Suburban Cook County and Chicago, the contingency plan is to increase bed capacity by doing the same things that were done in the spring, Gov. Pritzker said on Nov. 10.
Fifth: Number of Tests: The average number of tests per day in the last seven days is 101,285. This is higher than HGHI’s “mitigation” level testing target, but about only 50% of the amount needed to meet HGHI’s “suppression” level testing target. .
The number of new tests reported today was 77,136. This includes antigen tests.
Sixth: Delays in Getting Test Results: Public health experts convened by HGHI and Edmond J. Safra Center say test results should be obtained within 24 hours.
Dr. Ezike said on Nov. 12 that 53% of the lab tests come back in 48 hours, an indication that the results on almost half of the cases are coming in later. With the surge in the number of tests being administered, the lag time is getting longer, said Gov. Pritzker on Nov. 25.
A saliva test developed at the University of Illinois can produce results in 3 to 6 hours, and it is being used at U of I, Champaign.  Gov. Pritzker said the plan is to expand this method of testing across the State, especially to other college campuses.
The new antigen tests being distributed by IDPH can generate results in 15 minutes.
Seventh: Contact Tracing: Widespread contact tracing is also essential to control the spread of the COVID-19 virus. IDPH posted data on Nov. 27 showing the amount of contact tracing done in the period Aug. 1 through Nov. 21.
For Suburban Cook County, contact tracers attempted to interview 16% of the people who tested positive for COVID’19, and interviewed 12% of them. Of the close contacts identified by the people who tested positive, contact tracers attempted to call 62% and interviewed 55%
For Chicago, contact tracers attempted to interview 31% of the people who tested positive for COVID’19, and interviewed 16% of them. Of the close contacts identified by the people who tested positive, contact tracers attempted to call 61% and interviewed 34%.
Deaths: There were 66 deaths Statewide in the last 24 hours, and a total of 12,029 deaths due to COVID-19 during the pandemic.
For the last seven days the number of deaths in the State, as adjusted, are 127, 76, 47, 125, 155, 131 and 66 today.
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. “Previously, due to the limited number of antigen tests and limited information about antigen test accuracy, antigen tests were not included in the total number (which comprised less than 1% of total tests performed). Antigen tests, like BinaxNOW
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: https://globalepidemics.org/key-metrics-for-covid-suppression/
IDPH provides these categories and ratings: 1) “minimal” – less 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 calculated 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: https://coronavirus.jhu.edu/testing/testing-positivity
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%.
6/ How Much Testing Should be Done. The Harvard Global Health Institute posted a paper showing testing targets as of October 1, 2020. The targets for Illinois are 438 tests per 100,000 people to meet the “mitigation” target and 1,602 tests per day to meet the “suppression” target. The paper says that Illinois 7 day average of testing is 564 tests per day. Link to paper: https://globalepidemics.org/october-1-testing-targets/
Mitigation Level Testing: In an earlier paper, HGHI says for mitigation level testing, “The focus is on reducing the spread of the virus through broad testing of symptomatic people, tracing and testing a recommended 10 contacts per new case and isolating positive contacts, and social distancing, mask wearing or stay-at-home orders as necessary.
“There is a challenge with this approach: As states open up, mitigation level testing is often not sufficient to prevent new outbreaks.
“With strict social distancing orders in place, cases go down, but then spike back up again as a state loosens restrictions. It’s a rollercoaster of recurring outbreaks that creates great uncertainty, for example around reopening businesses, schools, and other vital parts of the economy.”
Suppression Level Testing: HGHI says, “Suppression level testing allows a state or community to quickly find and isolate new cases before they lead to a wider outbreak, with an aim of keeping new case levels at or near zero.
“This requires large, proactive testing — including regular testing of asymptomatic people in high-risk environments such as nursing homes, colleges, and parts of the service industry — paired with rapid contact tracing and supported isolation (TTSI), as well as other measures. Several states are working hard to build and maintain this type of response, including Massachusetts, New York and Connecticut.
“Suppression level TTSI programs reduce uncertainty and allow life to return to something closer to normal — but still include mask-wearing, social distancing, handwashing and other measures. It is easier to do when case counts are relatively low or on the decline.”
Link to HGHI’s report: https://globalepidemics.org/july-6-2020-state-testing-targets/
7/ Saliva-based Tests. On Aug. 19, the University of Illinois received emergency use authorization from the Food and Drug Administration to run a saliva-based COVID-19 test. “The saliva test is less expensive, faster, and requires significantly less raw materials than traditional testing,” said Gov. JB Pritzker. “If ongoing research continues to yield positive results, this has potentially game changing implications for our State-wide testing complex as well as for testing on a national level, particularly for our high risk communities and settings.
“This type of scalable product would allow us to mass deploy testing, and better track and contain the spread of COVID-19. We’re already working to deploy this to more public universities across the State over the next weeks and months and exploring rolling this out to do testing potentially for K-12 schools and even more testing at our long-term care facilities,” said the Governor.
Dr. Martin Burke, who put the research team together that developed the test, said that in a trial run in July, they were able to get “very fast test results, in many cases in 3 to 6 hours,” which enabled them to rapidly isolate people who were infected with the virus and to contact trace. They were able to reduce the test positivity rate from 1.5% to 0.2% during the month, he said.
Dr. Burke said “speed is the key.” The test is “very well suited to scalability” and the cost is about $10 a test. He added that the University has capacity to administer 20,000 tests a day. Link: https://evanstonroundtable.com/Content/City-News/City-News/Article/Illinois-rapid-saliva-test-for-COVID-19-now-operating-under-FDA-Emergency-Use-Authorization/15/26/18440