COVID-19: County Data

About our data

All data are laboratory-confirmed cases of COVID-19 that we freeze once a day to verify and ensure that we are reporting accurate information. These numbers are the official state numbers, though counties may report their own totals independent of DHS. Combining the DHS and local totals may result in inaccurate totals.

Data shown below are subject to change. As individual cases are investigated by public health, there may be corrections to the status and details of cases that result in changes to this information.

Deaths must be reported by health care providers, medical examiners/coroners, and recorded by local health departments in order to be counted.

The number of people with negative test results includes only Wisconsin residents who had negative test results reported electronically to DHS. As a result, this number underestimates the total number of Wisconsin residents with negative test results.

For information on testing, see: COVID-19, testing criteria section.

Download data by county | Data dictionary (PDF)

Mapped county-level data

 

This chart is called an epidemic curve (or "epi curve"). It is used to track the number of illnesses over time and see when peaks of illnesses occur. This figure is showing data by when someone's symptoms began, also called symptom onset date (or by diagnosis date if symptom onset date is missing, or the patient did not have symptoms). Symptom onset date is more meaningful than using the date when the case was reported because it represents when illnesses occurred, instead of when the person was tested and the result was reported to public health.

When using symptom onset date, any downward trends that are seen during the most recent two weeks are usually not true decreases in illness and need to be interpreted with caution. This downward trend usually represents the data lag time; thus, data during the most recent two weeks are highlighted as preliminary data. When people have an acute illness, such as COVID-19, it may take several days for them to see a doctor or be tested. It also takes time for the tests to be completed and the results to be sent to public health to be included in case counts.

The figure titled "Cumulative total and newly reported COVID-19 cases by date confirmed" on our COVID-19: Wisconsin Cases webpage does present data by the date a case was reported as being laboratory-confirmed (and not by symptom onset date). These data are also available by county and can be downloaded by clicking the "Download data by county" hyperlink above.

 

This chart is called a mortality curve. It is used to track the number of deaths over time and see when peaks occur. This figure is showing data by when a person died. Date of death is more meaningful than using the date when the person's death was reported to public health.

When presenting data by the date of death, any downward trends that are seen during the most recent two weeks are usually not true decreases in deaths and need to be interpreted with caution. This downward trend usually represents the data lag time; thus, data during the most recent two weeks are highlighted as preliminary data. It takes time for patient deaths to be reported to public health and to be included in death counts.

The figure titled "Cumulative total and newly reported COVID-19 deaths by date reported" on our COVID-19: Wisconsin Deaths webpage does present data by the date a death was reported as being associated with COVID-19 (and not by date of death). These data are also available by county and can be downloaded by clicking the "Download data by county" hyperlink above.

Number of positive cases and deaths by county

 
Last Revised: May 29, 2020

 RESPONSE RESOURCES FOR WISCONSINITES — www.dhs.wisconsin.gov/covid-19/help.htm