Respiratory Illness Data
Weekly Surveillance Summary
Key Points, updated 8/15/2025
- Overall acute respiratory illness activity level in Chicago remains Minimal, but with signs of increasing COVID-19 activity. National data suggest epidemic growth in Illinois and across the country.
- ED visits, hospitalizations, and ICU admissions for flu, RSV, and COVID-19 remain low across all age groups. However, ED visits for COVID-19 have been gradually increasing over the last several weeks, especially among children less than five years of age.
- COVID-19 test positivity continues to increase and is currently 5.7%. This is the highest level since January 2025. Test positivity rates for flu and RSV are unchanged and remain low.
- Overall wastewater concentrations for COVID-19 and RSV remain Minimal. Flu A concentrations increased from Minimal to Low and Flu B concentrations decreased from Low to Minimal.
- Parvovirus B19 activity has been increasing in Chicago and across the US. For information and guidance, see the July 10 Health Alert.
Respiratory Illness Dashboard
The Respiratory Illness Dashboard below summarizes information about respiratory virus disease activity in Chicago, with a focus on COVID-19 (caused by the SARS-CoV-2 virus), influenza, and respiratory syncytial virus (RSV). The dashboard will be updated every Friday at 1 p.m.
Additional Respiratory Illness Data
Find CDPH’s weekly surveillance report that tracks influenza, COVID-19, RSV, and other viral respiratory disease activity in Chicago.
Find information about how respiratory viruses are monitored in Chicago’s wastewater.
Learn more about how CDPH and the CDC are using genomic testing to monitor changes in diseases in Chicago.
Browse surveillance datasets that are available for download on the Chicago Data Portal.
Access health data for Chicago and your community.
The archived COVID-19 Data Dashboard is available for historical reference.
Archived data reports
National and State Respiratory Illness Data
