(Reuters) – The U.S. Centers for Disease Control and Prevention (CDC) on Tuesday released data on influenza A found in wastewater in a public dashboard that could help track outbreaks of H5N1 avian influenza that infected cattle herds.
Government officials told Reuters last week about the United States' plans to release data collected by the surveillance system.
Currently, the threat to humans from this virus is classified as low, but scientists are closely monitoring changes in the virus that could spread more easily among humans.
Testing wastewater from sewers has proven to be a powerful tool for detecting mutations in the SARS-CoV-2 virus during the COVID-19 pandemic.
For the week ending May 4, the agency's surveillance system showed no signs of unusual influenza activity in people containing the H5N1 virus. The virus has been detected in dairy cows in nine US states since late March.
The test detected unusually high levels of influenza A in Saline County, Kansas. The U.S. Department of Agriculture confirmed that four herds in Kansas have tested positive, the last confirmed case on April 17. Neither the state of Kansas nor the Department of Agriculture has released the county where the herd was located.
CDC is actively investigating multiple influenza indicators to monitor influenza A, of which H5N1 is a subtype, including He said that includes looking for signs of the virus's spread among people.
To monitor influenza A virus in wastewater, CDC will collect influenza A virus levels recorded at wastewater sites in recent weeks from October 1, 2023, to March 2, 2024 at the same wastewater site. compared to the levels reported in Anything above the 80th percentile is classified as high.
However, this test cannot determine the source of the virus or whether it came from infected birds, people, or milk.
“By tracking the percentage of specimens tested positive for influenza A viruses, we can identify abnormalities in influenza activity that may be early signs of the spread of novel influenza A viruses, including H5N1,” the CDC said in its report. “We can monitor a significant increase.”
Public databases allow individuals to see an increase in influenza A cases in their area or to spot unusual influenza activity.
(Reporting by Bhanvi Satija in Bengaluru; Additional reporting by Julie Steenhuisen and Tom Polansek in Chicago; Editing by Bill Berkrot)