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Wastewater surveillance may complement other existing human surveillance systems to monitor influenza. Wastewater data cannot determine the source of influenza A viruses. Detections could come from a human or from an animal (like a bird) or an animal product (like milk from an infected cow).
Wastewater Influenza A State and Territory Trends
Influenza A Wastewater Monitoring in the U.S.
This page shows the current wastewater viral activity level of influenza A for the overall state or territory. It also shows state/territory and national trends over time.
Current Site Levels – Link to Dataset (JSON) | Download Data (CSV)
Trend Over Time – Link to Dataset (JSON) | Download Data (CSV)
All State/Territory Wastewater Viral Activity Levels – Link to Dataset (JSON) | Download Data (CSV)
Wastewater monitoring can detect viruses spreading from one person to another within a community earlier than clinical testing and before people who are sick go to their doctor or hospital. It can also detect infections without symptoms. If you see increased wastewater viral activity levels, it might indicate that there is a higher risk of infection. See how to protect yourself from respiratory viruses.
About the Wastewater Viral Activity Level: The wastewater viral activity level indicates whether the amount of virus in the wastewater is minimal, low, moderate, high, or very high. The wastewater viral activity levels may indicate the risk of infection in an area. The wastewater viral activity levels are categorized as follows:
- Up to 1.6 – Minimal
- Greater than 1.6 and up to 4.5 – Low
- Greater than 4.5 and up to 12.2 – Moderate
- Greater than 12.2 and up to 20.1 – High
- Greater than 20.1 – Very High
National and state data represent the median values across all wastewater treatment plants. To learn more on how the wastewater viral activity level is calculated, see Data Methods.
Data Limitations: Wastewater data cannot determine the source of influenza A viruses. Detections could come from a human or from an animal (like a bird) or an animal product (like milk from an infected cow).
