The metrics are all moving in a positive direction. The Governor and IDPH are watching the data to see if
there will be an uptick or a surge in the coming weeks due to travel and gatherings over the holidays.
EVANSTON: 23 New COVID-19 Cases Today
There were 23 new confirmed COVID-19 cases of Evanston residents today.
The average number of new cases per day in the last seven days is 15.3. This is down from 30 on Dec. 21. For purposes of comparison, on Oct. 12, the seven-day average was 5.6.
There has been a total of 3,048 COVID-19 cases of Evanston residents during the pandemic, 406 of which are active. An accompanying chart shows the trend. [1]
In the last seven days, there was a total of 107 new COVID-19 cases of Evanstonians. That equates to about 142 new cases per 100,000 people in the seven-day period. This is down from 279 for the prior week. The State’s seven-day target is 50 per 100,000.
The test positivity rate for new cases in the last seven days is 3.1%. 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 94.
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 Dec. 14 and Dec. 20, there were 28 new confirmed COVID-19 cases of faculty, students. 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. [2]
KEY METRICS FOR 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 816 new COVID-19 cases today, and 772 in Chicago, for a total of 1,588.
In the State, there were 4,453 new cases reported today.
Statewide, the average number of new cases per day in the last seven days is 5,327. This is down from an all-time high of 12,380 on Nov. 17, and also down from the seven-day average of 6,990 one week ago on Dec. 21. This is the 18th day in a row that the seven-day average has declined. 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 high in the spring. The seven-day average today is still more than double 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. Two leading research groups say there is “accelerated spread” if the number is over 70. [3]
In the seven days ending Dec. 28, the number of new cases per 100,000 people were as follows for the areas indicated:
– Suburban Cook County: 281 (compared to 344 on Dec. 21)
– Chicago: 241 (compared to 333 on Dec. 21)
– Illinois: 294 (compared to 386 on Dec. 21)
For each area, the number of new cases per 100,000 on Dec. 28 is significantly lower than they were on Dec. 21, but they are each significantly higher than the benchmarks. [4]
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 are as follows:
– Suburban Cook County: 9.0% (as of Dec. 25)
– Chicago: 8.2% (as of Dec. 25)
– Illinois: 8.7% (as of Dec. 28)
Each positivity rate is much higher than the targets. An accompanying chart highlights the rates.
Fourth, Hospital Admissions and Surge Capacity. There were 2,133 hospitalizations due to COVID-19 in Suburban Cook County and Chicago as of midnight on Dec. 27. By way of comparison, hospitalizations in the regions were 2,836 on Dec. 1.
IDPH reported that, as of Dec. 27, Suburban Cook County had a surplus capacity of 27% of medical/surgical beds and 20% of ICU beds; and Chicago has a surplus capacity of 25% of medical/surgical beds and 26% of ICU beds. IDPH’s target is 20% surplus capacity.
On a Statewide basis, the number of hospitalizations due to COVID-19 was 4,243 as of midnight on Dec. 27. They are down from an all-time high of 6,171 on Nov. 23. A chart in the chart box shows the trend.
The number of patients using ICU beds is 854, down from 1,195 on Dec. 1. The number of patients on ventilators is 515 down from 724 on Dec. 1.
Deaths: On a Statewide basis, there were 105 deaths due to COVID-19 in the last 24 hours, which brings the total to 16,024.
For the last seven days, the number of deaths in the State were 116, 135, 96, 156, 66, 104, and 105 today. The seven-day average is 111. For purposes of comparison, the seven-day average on Dec. 7 was 153.
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FOOTNOTES
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%.