Monmouth College is located in Monmouth, Illinois which is the county seat for Warren County, Illinois. Like the rest of the globe, we’ve been spending the summer trying to navigate the COVID-19 Coronavirus pandemic. The college ended in-person instruction in early April of 2020 when the state of Illinois entered a general lock-down asking residents to, wherever fesiable, work from home, stay home, and hunker down to slow the spread of the virus. It’s now early August, the virus is still present within our community and the college is preparing to welcome 800+ students back to campus for a mixture of in-person and online instruction. The Monmouth-Roseville public school district has declared that K-12 classes will all be held remotely this fall. With kids in that school district, I find myself stuck between a school exhibiting caution and a school exhibiting optimism. I’ll admit I prefer caution and will be teaching my students remotely this Fall.

When cases began to show up in our county, the Warren County Health Department issued reports via their website and social media. Initially these reports only listed new cases along with some rough demographics of the infected individuals. The first such report came out on April 10. By April 22 the reports contained not only the number of confirmed cases but the total number of negative and positive tests reported thus far. These reports provided not only a sense of the prevalence of the virus’ spread within the community but also a window into the testing policies employed by local health officials. Starting on May 10th, the health department began to report on the number of infected individuals whose “symptoms have resolved”. At this time the county health department continues to report the following metrics: newly confirmed cases, demographics of new cases, total negative tests to day, total positive tests to date, and the total number of individuals whose symptoms have resolved.

I began recording the data from the health department reports not too long after they began issuing them. One day we’d have a few new cases, the next none, the day after that a few more, and so on. I wanted to better understand the trend and the day to day reporting lacked that context and started making basic visualizations of the data. It seemed reasonable to assume that other people in the community would be interested in seeing this presentation of our little corner of the pandemic so I started posting them on Facebook and sharing them with co-workers at the college. To this day, have continued to provide weekly updates on the state of the virus in our county and region. The Facebook posts are all public if you care to find them.

Going forward, I plan to move my reports off of Facebook and to this space. I’ll post links to reports done on this website to social media but will keep the actual content here. Doing so helps me keep a better record of my reporting and lets me provide better, more interactive visuals for others. This post is the flashback episode. It covers all the data from the first case in the county to the end of July and is largely a recap of what I’ve been sharing on Facebook to date.

A Note on Data

I get my data from three publicly available sources. The first is the Warren County Health Department. As described above, they provide daily reports on test results, demographics of the infected, and status of the infected. Most of what you see in this post comes from these reports. My second source of data is They are a non-partisan, non-profit focused on maintaining and sharing data for the public good. They have been gathering and reporting county level data on confirmed cases and deaths. Much of it seems to be gathered manually by checking with county health departments all over the country. As a result, it lags behind just a little. This data is crucial for understanding how what we’re experiencing in Warren County compares to other places in the country. It also has allowed me to report on the status of the pandemic in the region surrounding Warren County. I’ll post a recap of this data in another blog entry. My final data source is the Illinois Department of Public Health. They too provide county level data but not in a form that you can download. I mostly use them to record regional metrics, notably the positive test rate, in order to compare our county to the other counties we’ve been grouped with as part of the state’s recovery plan. This data also lags behind by a few days.

COVID-19 in Warren County, Illinois: April 2020 - July 2020

Our town boasts around 9000 of the Warren County’s 16844 residents. Our first case was reported by the health department on April 10th. On April 17th the health department confirmed that multiple employees of the Smithfield pork processing plant in Monmouth had tested positive. Like many counties in the United States, we saw a sudden surge of cases that traced back to a local meat packing plant. Smithfield briefly shut down operations, setup measures to prevent continued spread, and instituted voluntary testing for its employees upon reopening. By mid May the plant was back up and running and the spread of the virus had slowed down.

In April the Governor of Illinois declared a state of emergency, instituted extreme social distancing measures, and eventually laid out a plan by which these restrictions could be relaxed. The Restore Illinois plan has five phases. The first phase is marked by rapid spread of the virus, the second by flattening of the new case curve, the third by slow recovery, the fourth is focused on revitalizing the economy, and the fifth is a return to something a bit more like the pre-pandemic normal. When the plan was announced we were already in Phase 2. On May 29, we moved to Phase 3 and on June 26, we moved to Phase 4. The state is still in Phase 4 and, like much of the country, we are fighting new surges in the spread of the virus.

Daily New Cases

The data lets us go back to the beginning and see the number of new cases reported on a day to day basis. Below you see this data presented visually. Each bar is the number of new cases reported that day. The bars are colored based on which phase of the recovery plan we were in a the time. Included as a trend line on this graphic is the seven day average of new cases. By mousing over a bar you can see the number of new cases that day as well as the average number of cases for that day and the six days preceding it.

With this graph you can really see the initial surge in April, the post lock-down quiet period in June, and the steady increase in cases that has come along with relaxed social distancing during phase 4.

Daily Testing

It’s important to look not just a new cases but overall trends in testing. One of the main reasons I started recording this data is because I wanted to know how many tests were being done on a daily basis. The health department told us the total number of negative tests and new positive tests and leaves things like determine totals tests for the day and positive test rate as an exercise for the reader. I did the math.

These data begin on April 22 because the health department reports did not include negative test data prior to that date. You can see a cluster of peaks in early May. These are presumably the result of voluntary testing at the Smithfield plant when it reopened. On July 25 we see a massive number of tests reported. The health department confirmed that these were the result of state mandated testing in long-term care facilities. By and large, the county has only be testing symptomatic individuals. It is my understanding that close contacts of infected individuals are asked to monitor symptoms and are not tested if they are asymptomatic. It’s also important to keep in mind that any individual who has had multiple tests done will show up in this data more than once. Finally, tests are counted according to the county of residence of the tested individual. If someone lives in Knox county, works in Warren County, and is tested in Henderson County, then their result is included in the Knox County data. In a nutshell, these numbers tell us about tests carried out on residents of warren county, period.

Health department reports include total positive and negative tests so it’s worth looking at this cumulative picture of testing as well.

Positive Test Rate

To put testing numbers in context we can look at the positive test rate. Currently, the state of Illinois considers anything at or above 8% to be problematic. If your county or region reports a rate in this range for three days straight, then you are at risk of seeing social distancing measures increase. Alternatively, if seven of the last 10 days saw an increase in the positive test rate and your local hospital system is seeing a comparable increase in COVID-19 like admittance, then you might get a mandate for increased social distancing as well.

The graphic below tracks our county’s positive test rate since April 22. Once again, bars are colored by recovery phase and the line represents the seven day average. The clear outlier here is June 21. On that day we had a 100% positive rate because there was only one positive test in that report.

The Status of those Infected with COVID-19

On May 10 the health department began to report on cases whose symptoms had resolved. To date there have been zero reported deaths and it does not appear to be the practice to retest people that have previously tested positive to see if they still carry the virus. This leads to the lovely turn of phrase, “symptoms have resolved”. What this means in practice is that individuals who have tested positive are declared recovered if they have gone 10-14 days without symptoms of active infection.

On the graphic below you can see cases going back to April 22. Starting on May 10 the number of cases is split into active and resolved.


The health department groups cases by sex and age and reports this information to the public. Age is clustered into broad ranges: 0-10, 10-20, 20-40, 40-60, 60-80, and 80-100. The graphic below covers all the cases up through and including the month of July.

Next Up: Regional Comparisons

The data presented here sheds light on what’s happening in Warren County. The data lets us compare what we’re experiencing to other counties across the united states. My Facebook reports have often included a look at how we compare to nearby counties in Illinois and Iowa as well as snapshots of our Illinois recovery region. In my next post I’ll do a recap of this data from the start of the pandemic through the end of July.