The Centers for Disease Control and Prevention (CDC) has recently introduced a new tool to monitor influenza A in wastewater, specifically focusing on the H5N1 avian influenza strain. This initiative comes as three states have reported increased detections of H5N1 in dairy herds, raising concerns about potential asymptomatic spread among dairy cows.

Due to the challenges of delayed and inconsistent testing in dairy herds, experts are exploring alternative methods like wastewater surveillance to enhance the understanding of H5N1 transmission pathways. The CDC’s new influenza A wastewater dashboard, featured on its H5N1 monitoring page, aims to provide insights into the spread of the virus.

The dashboard utilizes an interactive map to display current influenza A levels in comparison to the previous season, highlighting areas where levels are notably high. At present, 230 sites across 34 states have met the data reporting criteria, with three sites in Kansas, Florida, and Illinois showing elevated levels of influenza A.

Experts in the field have expressed support for the CDC’s efforts, emphasizing the importance of monitoring suspiciously high samples for H5N1. Dr. Marc Johnson from the University of Missouri commended the dashboard for its transparency, while Dr. Brian Wasik from Cornell University highlighted its role in identifying trends and research targets.

In parallel developments, the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) reported four new H5N1 detections in dairy herds, bringing the total to 46. These detections were concentrated in states already affected by the virus, with Michigan, Texas, and Idaho each reporting new cases.

Furthermore, APHIS identified three additional H5N1 detections in wild birds, including two in counties with previously affected dairy herds. These findings underscore the interconnected nature of H5N1 transmission between wildlife and livestock populations.