The number of new people who tested positive for COVID-19 in Illinois during the last 24 hours jumped to 3,137 people. In addition, the percentage of people who tested positive on the tests was 21.2%, a sign that there may be many more people with COVID-19 in the community who have not yet been tested.

Governor J.B. Pritzker laid out an ambitious plan to contact trace people who test positive for COVID-19, with a price tag of about $80 million. Contact tracing is a key element to open the economy.

Measures to Open the Illinois Economy

One measure being used to determine if the economy is ready to open is whether the number of COVID-19 infections and/or the number of hospitalizations has peaked and has shown a downward trajectory for 14 consecutive days. In the last 10 days, Governor J.B. Pritzker has seemed to put his focus on the trend in hospitalizations.

Gov. Pritzker has also repeatedly said that other measures include whether testing, tracing and treatment are in place. In addition, he says it is critical that an adequate amount of Personal Protection Equipment (PPEs, e.g., face masks, gowns, etc.) be available.

Below is data showing the trends in infections, hospitalizations, and testing.

The Number of Infections and Hospitalizations

Evanston: The number of Evanston residents who have tested positive for COVID-19 increased by 19 cases today, May 1, for a total of 357 cases, according to information provided by the City of Evanston. The trend is shown in the above chart. 

To date, a total of 10 Evanstonians have died due to COVID-19.    

Chicago, Cook County and Illinois: For Chicago, the number of confirmed COVID-19 cases grew from 21,491 yesterday to  22,718 today; the cases in Cook County grew from 36,593 yesterday to 38,668 today; and the number of cases in Illinois grew from 52,918 yesterday to 56,055 today. The trend is shown in the first chart in the chart box.

Dr. Ngozi Ezike, the Director of Illinois Department of Public Health, said that there were 3,137 new confirmed cases reported in the last 24 hours in Illinois. This is the highest number of new cases thus far. The trend of new cases is shown in the second chart in the chart box.

The rate of increase of new cases, in relation to the total cases as of the prior day, was 4.7% on April 29, 5.1% on April 30, and 5.9 % today.

The number of deaths in Illinois due to COVID-19 increased by 105 in the last 24 hours, bringing the total number of deaths due to COVID-19 in Illinois to 2,355.

Hospitalizations in Illinois: Dr. Ezike reported that the number of hospitalizations due to COVID-19 in Illinois was 4,900 today, down from 4,953 on April 30 and 5063 on April 29. The number of COVID-19 patients occupying ICU beds was 1,263 today, down from 1,289 and 1,290 in the prior two days. Today 777 people are on ventilators, compared to 785 and 777 people in the prior two days.   

The State’s hospitals have capacity to handle these numbers of patients. As of April 25, there were 11,173 hospital beds open, 966 ICU beds open, and 1,894 ventilators available.

Adequacy of Testing

There are two measures to assess the adequacy of testing discussed by researchers: 1) the number of tests given in relation to the population; and 2) the percentage of people who test positive for COVID-19.

The Number of Tests in Illinois

Both Gov. Pritzker and Dr. Ezike have repeatedly said that testing is critical to opening up the economy and to do so in a manner that protects the health and safety of the people. More than a month ago, Gov. Pritzker established a goal to give 10,000 tests per day. Last week, the State surpassed that goal, but both he and Dr. Ezike say that more testing is needed. They have not yet set a new goal. 

In the first five days of April, there was an average of 5,152 COVID-19 tests administered in Illinois each day. In the last five days of April, there was an average of 13,650 COVID-19 tests administered in Illinois each day. On May 1, the number of tests reported in the prior 24-hour period was 14,821 tests.

The number of COVID-19 tests in Illinois has gone up substantially.

Some researchers say that on a nationwide basis the minimum number of COVID-19 tests to safely open the economy is 500,000 per day, which would require about 150 tests for every 100,000 people.*

For Illinois to meet that target, it would need to give about 19,500 tests per day. While making progress, Illinois is still short of that benchmark.

Some researchers put the number of tests needed at more than ten times that amount.**

The Percent Positive Test Rate

There are many undiagnosed cases of COVID-19 because there has been limited testing capacity. Both Gov. Pritzker and Dr. Ezike have acknowledged that that confirmed number of COVID -19 cases reported daily by IDPH grossly understates the actual number of COVID-19 cases, because it does not capture people who have shown mild symptoms, or who are asymptomatic and who have not qualified for testing.

One measure used by researchers is to assess whether the amount of testing is adequate is to look at the percent of people who test positive on COVID-19 tests. The World Health Organization suggests that a test positive rate should be between 3% and 12%. A test positive rate over 10% likely reflects that there is an inadequate amount of testing and that it should be increased to cast a wider net.***

In the first five days of April, there was an average positive test rate was 20.4%. In the last five days of April, the average positive test rate was 16.3%.

On May 1, the test positive rate was 21.2%. The trend is shown in the third chart in the chart box.

The test-positive rate is still above 10%.

The Plan for Contact Tracing in Illinois

“Contact tracing is one of the most critical tools that we have to reduce our spread rate, speed up our diagnosis and seek to halt outbreaks before they happen,” said Gov. Pritzker.

He summarized the plan to conduct contact tracing in Illinois.

“Contact tracing isn’t a new concept,” he said. “It’s been around for many years. The difference now is that in order to move safely back toward normalcy, Illinois, the United States, and, frankly, the whole world must contact trace on a never before seen scale.”

Gov. Pritzker generally described the process.

First, he said, “When an individual tests positive for COVID-19, a contact tracer will reach out to them through an app, through email, a text, or a phone call. And because not everybody can or will use technology, some will require follow-up even with a safe in-person visit, if the COVID positive person can’t be reached in some other way.

“Then, step two, interviewing the COVID positive person asking them to gather their contacts and retrace their steps over the past 14 days. This is what allows us to significantly slow the spread of the virus. Because connecting with those who’ve been exposed allows us to do three important things.

  • One, notify them that they’ve recently been in proximity of someone who has tested positive.
  • Two, recommend that they seek a test and self-isolate.
  • And three, offer them resources on how to access any needed assistance to prepare them for self-isolation, things like alternative housing, food delivery or medication.

“Privacy is an important aspect of maintaining trust in contact tracing,” the Governor added. “So to be clear, contacts will remain anonymous.

Gov. Pritzker said local health departments have been using contact tracing techniques since the earlies days of the COVID-19 pandemic. They have aggressively sought out each COVID-19 positive person to identify all their close contacts, and then encouraged those contacts to opt into monitoring programs and to follow recommendations.

He said, though, that the public health management infrastructure has not been able to keep pace with the massive scale of the spread, pointing out that there are more than 50,000 confirmed cases of COVID-19. “Their contacts are 50,000 sets of family, friends, co-workers, commuters, classmates, and other contacts. It’s an unprecedented public health challenge. So we need an unprecedented solution to meet this moment.

“To do that, Illinois will be building on our existing infrastructure and expertise to shape a massive statewide contact tracing operation, gradually building over the coming weeks, and then scaling up an army of contact tracers by the hundreds, and then by the thousands.”

Dr. Wayne Duffus, the Acting Chief Epidemiologist for the State, has primary responsibility for contact tracing. He said contact tracing is a core public health activity that has been practiced since the early 19th century.

“In the context of COVID-19,” he said, “it is the process of following up with contacts who may have been exposed to a person with suspected or confirmed infection.”

Contacts are self-quarantined for 14 days from the date of last exposure. They are eligible for testing, and if the testing shows they are not infected, they will be released from isolation.

Dr. Duffus said the State’s local health departments have well-trained staff who utilize the principles of contact tracing on a daily basis in their work. They use it in tracing HIV infections, syphilis, and tuberculosis. “This makes the local health departments the ideal core essential partner to serve as a hub of our activity in Illinois.”

He said the local health departments will work with community health centers, and the State will act as the umbrella to ensure consistency.

Dr. Duffus said workers will be hired from around the State, and they are using an estimate that 30 workers will be needed for every 100,000 people in the State, which means 3,810 people to carry out the program. He said this number will vary over time.

“The core personnel for contact tracing efforts lies in three cadres,” said Dr. Duffus. “First, case investigators. These are the individuals who reach out to people who get positive test results. Second, contact tracers. They will call individuals who have been in close contact with a diagnosed case and ensure adherence to protocol, follow-up as necessary. The third cadre are resource coordinators, and these resource coordinators provide individuals quarantined or in isolation with reasonable relevant resources and support to facilitate compliance with our orders, so food, medication, alternate housing for example.”

Dr. Duffus said they will start out with 300 workers, strategically placed in the regions that are most impacted. In addition by using technology as a first contact with individuals, the number of workers needed will be fewer. “We plan to implement a virtual Call Center, which will enhance efficiencies and only the most hard to reach individuals will actually require a visit.”

Dr. Duffus said they would like to start by the end of the month.

Gov. Pritzker said the cost would be about twice what Massachusetts has budgeted, or “somewhere in the neighborhood of $80 million.”



*Ashish Jha, MD, MPH, the Faculty Director of the Harvard Global Health Institute, and two colleagues conclude in an April 18 article “Why we need at least 500,000 tests per day to open the economy – and stay open,” that on a nationwide basis at least 500,000 tests a day are needed to succeed with the opening of the economy and to stay open. They add that number “is probably too low” and “we likely need many more.” Link:

That is about triple the number being administered now, and it would require about 150 tests per day per 100,000 people.

** Other researchers put the number much higher. A report, “Roadmap to Pandemic Resilience,” published by the Edmond J. Safra Center for Ethics at Harvard University, recommends massive scale testing for COVID-19, together with supported isolation as the path to open up the nation’s economy. The report, updated on April 20, has 23 authors, with expertise in many different disciplines.

The Safra Center report says, “We need to deliver 5 million tests per day by early June to deliver a safe social reopening. This number will need to increase over time (ideally by late July) to 20 million a day to fully remobilize the economy.” Link:

*** See article cited above by Ashish Jha.

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...