Researchers developed and deployed a test that confirmed the presence of bird flu in Texas wastewater treatment plants days before outbreaks in cattle were officially confirmed.
Wastewater surveillance can be used to monitor for outbreaks of strains of influenza that affect animals, known as zoonotic influenza.
Monitoring for zoonotic influenza in wastewater could allow public health experts to identify and respond to human outbreaks earlier.


Bird flu was detected in wastewater before the first reported outbreak among Texas dairy cattle in 2024, according to new findings presented at IDWeek 2024. Experts say early detection of infectious disease outbreaks is vital to enable timely and effective public health responses to bird flu and other zoonotic influenza.

Researchers found a biomarker for bird flu in Texas wastewater treatment plants days before outbreaks were reported in cattle. Two of three wastewater treatment plants with bird flu biomarkers confirmed animal protein had already left processing facilities, including dairy farms.

The researchers sought to explain unseasonal increases in influenza A virus seen in Texas wastewater treatment plants early this year. Researchers designed and distributed to wastewater treatment plants a test for the H5 hemagglutinin gene found in bird flu. Clinical data on influenza-related health care visits were used to compare influenza A virus increases in wastewater with confirmed cases of influenza in humans.

“Every second counts when responding to emerging pathogens — that’s why wastewater surveillance is a critical tool in the public health toolbox,” said Alessandro Zulli, PhD, postdoctoral fellow at Stanford University and presenting author of the study. “Expanded use of wastewater surveillance will give public health professionals the early warning system they need to address emerging infectious diseases threats.”

The researchers say the findings demonstrate the utility of wastewater surveillance as a tool to track zoonotic influenza in agricultural facilities. Broader use of wastewater surveillance for zoonotic influenza could provide an early warning of outbreaks before symptoms appear in livestock or humans, they wrote.

In addition to Dr. Zulli, study authors include: Marlene Wolfe, MSc, PhD, and Alexandria Boehm, MS, PhD.