The accompanying charts show that the seven-day averages of new COVID-19 cases have been declining in Suburban Cook County, Chicago and Illinois. The numbers of new cases, though, are still very high – in the range where aggressive community spread is still a risk. Hospitalizations have been coming down, but also remain high. The number of deaths in the State reported in the last 24 hours was 181.
The seven-day trends in Evanston have been more erratic.
Gov. JB Pritzker, said today, “Let’s be clear we are in terms of cases, in terms of hospitalizations, in terms of ICUs, those numbers do seem to be heading in the right direction.
“We’re very glad that things are moving in the right direction,” he said, but added, “We’re also concerned the numbers have not come down as precipitously as we would have liked to have seen by now. And so, that’s of great concern to us. We’re still seeing 7,000, 8,000, 9,000 cases every day. And we still have a positivity rate that’s far from the WHO recommended 5%.”
He said what happens over the holidays will have “an enormous effect on whether we can bring down the Tiers from Tier three to Tier two and beyond. But that’s what we’re focused on every day.” He said after the holidays they will look at whether they can reduce the restrictions in some of the Regions in the State.
Dr. Ngozi Ezike, Director of the Illinois Department of Public Health, said, “I am really happy to say that we did not see the significant surge that we were very much concerned about” following Thanksgiving. She said there were surges of cases in other parts of the country and thought the mitigations put in place in Illinois before Thanksgiving helped.
Gov. Pritzker reported that an independent advisory committee of the FDA endorsed the Moderna vaccine yesterday for adults 18 and over. He said the Moderna vaccine is 94.1% effective after two doses administered four weeks apart, and that it is proven safe in clinical trials. He said the FDA may approve the vaccine as early as today.
The Governor said, “Our own vaccine advisory panel is poised to review all available FDA data, assuming a favorable outcome, and based upon the federal government’s likely delivery schedule, Illinois hospitals can expect their Moderna shipments sometime early next week.
“This is yet another very exciting development. And it reinforces and it brightens the light at the end of the tunnel for all of us who have been fighting through COVID-19.”
After the briefing by Gov. Pritzker, the FDA approved Moderna’s vaccine.
EVANSTON: 25 New COVID-19 Cases Today
There were 25 new confirmed COVID-19 cases of Evanston residents today.
The average number of new cases per day in the last seven days is 31.1. For purposes of comparison, on Oct. 12, the seven-day average was 5.6.
There has been a total of 2,871 COVID-19 cases of Evanston residents during the pandemic, 429 of which are active. An accompanying chart shows the trend. 
In the last seven days, there was a total of 218 new COVID-19 cases of Evanstonians. That equates to about 290 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 6.3%. The rate is up from 2.8% on Nov. 1.
No Evanstonian died due to COVID-19 in the last 24 hours. The number of deaths due to COVID-19 remains at 91.
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. 
Northwestern University has posted data on its website reporting that between Dec. 11 and Dec. 17, there were 17 new confirmed COVID-19 cases of staff (8) and students (9). The number includes those who live outside of Evanston. 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. 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 1,374 new COVID-19 cases today, and 1,385 in Chicago, for a total of 2,579, down from 3,114, yesterday.
In the State, there were 7,359 new cases reported today.
Statewide, the average number of new cases per day in the last seven days is 7,691. This is down from an all-time high of 12,380 on Nov. 17, and also down from the seven-day average of 8,974 one week ago on Dec. 11. While the trend has been declining, 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 almost 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 and 168. 
In the seven days ending Dec. 18, the number of new cases per 100,000 people was as follows for the areas indicated:
– Suburban Cook County: 385 (compared to 97 on Oct. 1)
– Chicago: 388 (compared to 86 on Oct. 1)
– Illinois: 423 (compared to 111 on Oct. 1)
The new cases in each area are more than seven times IDPH’s target.
An accompanying chart shows the trend in the number of new cases during the week ending Dec. 18, compared to the number of new cases for the weeks ending Oct. 1 and Dec. 11. 
The chart shows that the number of new cases per 100,000 on Dec. 18 are down from where they were on Dec. 11 for Chicago, Suburban Cook County and the State.
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 seven-day test positivity rates are as follows:
– Suburban Cook County: 11.9% (as of Dec. 15)
– Chicago: 12.0% (as of Dec. 15)
– Illinois: 9.7% (as of Dec. 18)
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 2,419 hospitalizations due to COVID-19 in Suburban Cook County and Chicago as of midnight on Dec. 17, up from 1,456 on Nov. 1. The number of hospitalizations has, however, gone down by more than 400 since Dec. 1.
IDPH reported that, as of Dec. 17, Suburban Cook County has a surplus capacity of 17% of medical/surgical beds and 17% of ICU beds; and Chicago has a surplus capacity of 16% of medical/surgical beds and 20% of ICU beds. IDPH’s target is 17% surplus capacity.
On a Statewide basis, the number of hospitalizations due to COVID-19 was 4,690 as of midnight on Dec. 17. This is 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 1,023, up from 347 on Sept. 1. The number of patients on ventilators is 589, up from 142 on Sept. 1.
Deaths: On a Statewide basis, there were 181 deaths due to COVID-19 in the last 24 hours, which brings the total to 15,015.
For the last seven days, the numbers of deaths in the State are 127, 115, 103, 117, 145, 180, and 181 today. The seven-day average is 138. 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: https://globalepidemics.org/key-metrics-for-covid-suppression/
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: 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%.