Wastewater COVID-19 State and Territory Trends

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 very low, 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 1.5 – Very Low
• Greater than 1.5 and up to 3 – Low
• Greater than 3 and up to 4.5 – Moderate
• Greater than 4.5 and up to 8 – High
• Greater than 8 – Very High

CDC’s Respiratory Illnesses Data Channel recently updated the label of “minimal” to “very low” to improve clarity and better communicate the severity levels associated with respiratory illness activity. CDC’s wastewater data for Influenza A, RSV, and COVID-19 reflect this label change.

No Data: States or territories without sufficient data to estimate the wastewater viral activity level for the previous week are indicated as “No Data.” A label of “No Data” means that either: 

• No data were reported this week from sites within the state or territory 

• Data were reported this week, but sites within the state or territory do not have enough data (at least 6 weeks with consistent methodology) to estimate the Wastewater Viral Activity Level in the last week.   

National, regional, and state/territory data represent the median values across all wastewater treatment plants in the respective area. To learn more on how the wastewater viral activity level is calculated, see Data Methods.

Trends Over Time Graph Regions: When you select a state/territory, the region line corresponds to the region that state belongs to. States and territories are grouped into the following U.S Census Bureau regions:

• West: Alaska, Arizona, California, Colorado, Guam, Hawaii, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, Wyoming (N=14)
• Midwest: Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, Wisconsin (N=12)
• Northeast: Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Puerto Rico, Rhode Island, Vermont (N=10)
• South: Arkansas, Alabama, Delaware, District of Columbia, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, West Virginia (N=17)