This evening, School District 65 Superintendent Devon Horton announced that the School District 65 will delay opening its schools for in-person learning past Jan. 19. He said the District is not meeting the health metrics on any front. He mentioned that Suburban Cook County has not had a rolling positivity rate lower than 8% for three consecutive days, and that the District has been looking for a 3% or lower positivity rate for its attendance area zip codes. Evanston’s test positivity rate was 4.1% today. See accompanying story.
EVANSTON: 29 New COVID-19 Cases Today
There were 29 new confirmed COVID-19 cases of Evanston residents today.
The average number of new cases per day in the last seven days is 18.7. This is up from 14.3 on Dec. 29. For purposes of comparison, on Oct. 12, the seven-day average was 5.6.
There has been a total of 3,190 COVID-19 cases of Evanston residents during the pandemic, 330 of which are active. An accompanying chart shows the trend. 
In the last seven days, there was a total of 131 new COVID-19 cases of Evanstonians. That equates to about 174 new cases per 100,000 people in the seven-day period. This is up from 133 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 4.1%. The rate has increased from 2.9% on Dec. 29.
One Evanstonian died due to COVID-19 in the last 24 hours. The number of deaths due to COVID-19 is now 96.
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. 28 and Jan. 3, there were 18 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. NU’s test positivity rate is 9.28%. 
KEY METRICS FOR SUBURBAN COOK COUNTY, CHICAGO, AND ILLINOIS
Several key metrics used by the Illinois Department of Public Health (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. Others are the capacity of hospitals to care for a surge of new patients and the number of deaths.
First, New Cases. The seven-day averages of new cases have increased for Suburban Cook County, Chicago and the State.
In Suburban Cook County, there were 1,334 new COVID-19 cases today, Jan. 5. The seven-day average is 1,117, compared to 952 for the week ending Dec. 29, or an 17% increase from week to week.
The number of new cases in Chicago was 1,202. The seven-day average is 1,113, compared to 909 for the week ending Dec. 29, or a 22% increase.
In the State, there were 6,839 new cases reported on Jan. 5, which is the seventh consecutive day that the number of cases has increased.
Statewide, the average number of new cases per day in the last seven days is 6,244, compared to 5,171 for the week ending Dec. 29, or a 21% increase.
The all-time high seven-day average for the State is 12,380 on Nov. 17. While new cases have declined significantly from then, the number of new cases is still 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. 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. 
In the seven days ending Jan. 5, the number of new cases per 100,000 people were as follows for the areas indicated:
– Suburban Cook County: 316 (compared to 270 on Dec. 29)
– Chicago: 287 (compared to 235 on Dec. 29)
– Illinois: 345 (compared to 286 on Dec. 29)
For each area, the number of weekly new cases per 100,000 on Jan. 5 is higher than on Dec. 29. The numbers of new cases are each significantly higher than the benchmarks. 
Third, a Test Positivity Rate. IDPH’s target is that the test positivity rate be 5% or less, although Harvard Global Health Initiative (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: 9.9% (as of Jan. 2)
– Chicago: 10.0% (as of Jan. 2)
– Illinois: 9.8% (as of Jan. 4)
Each positivity rate is higher than the targets. An accompanying chart highlights the rates.
Fourth, Hospital Admissions and Surge Capacity. There were 1,957 hospitalizations due to COVID-19 in Suburban Cook County and Chicago as of midnight on Jan. 4. By way of comparison, hospitalizations in these regions were 2,836 on Dec. 1.
IDPH reported that, as of Jan. 4, Suburban Cook County had a surplus capacity of 22% of medical/surgical beds and 23% of ICU beds; and Chicago had a surplus capacity of 21% 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 3,905 as of midnight on Jan. 4. 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 800, down from 1,195 on Dec. 1. The number of patients on ventilators is 457, down from 724 on Dec. 1.
Deaths: On a Statewide basis, there were 126 deaths due to COVID-19 in the last 24 hours, which brings the total to 16,959.
For the last seven days, the numbers of deaths in the State were 198, 133, 155, 29, 81, 79, and 126 today. The seven-day average is 114. For purposes of comparison, the seven-day average was 153 on Dec. 7.
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.”
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%.