Influenza (flu) is a contagious illness caused by influenza viruses. Flu primarily affects the respiratory tract (e.g., nose, throat, chest, and lungs). The resources found in these web pages provide information for health professionals and the general public to help reduce the spread of flu in Iowa. The best way to reduce the risk of flu and its possible serious consequences is to get vaccinated for flu every year.  See the Iowa HHS influenza vaccine page for more information.

Individual cases of influenza are not reportable in Iowa although the Iowa Department of Health and Human Services (Iowa HHS) does require that cases of novel influenza and influenza outbreaks be reported. As most cases of flu are not reported, Iowa HHS relies on voluntary reporting from laboratories, schools, vital records, hospitals, care facilities, and outpatient health clinics to monitor influenza activity in Iowa. Please contact Andy Weigel at andy.weigel@hhs.iowa.gov to find out more about becoming a surveillance site. The Iowa HHS influenza program summarizes all flu data along with some other viral respiratory illnesses in regular surveillance reports.

Respiratory webinar slides for the 2025-26 influenza season

Respiratory Reports

Sign up to receive the weekly respiratory virus surveillance report.  This email is sent out before the report is posted online, so if you need immediate access to the latest report be sure to subscribe.

Current Issue

Respiratory Virus Report - Week 46, 2025

List items for Respiratory Virus Reports

Prior flu reports are available on Iowa Publications Online

List items for IISN

See below for information about how to report and respond to illness outbreaks in specific populations.