CDC unveils dashboard to track bird flu as virus spreads among dairy farms

The U.S. Centers for Disease Control and Prevention (CDC) has introduced a new dashboard to help track the spread of bird flu, as part of the federal government’s effort to monitor and control the virus. Although the virus has primarily impacted dairy cows and hasn’t posed a significant threat to humans yet, its ability to jump between species has prompted the CDC to enhance its response.

The new dashboard includes various data sets, such as information on wastewater sampling sites that have tested positive for influenza A, which includes the avian influenza subtype H5N1. The dashboard presents data through graphs and charts, allowing comparisons of positive tests in different regions over the past year.

“By monitoring the percentage of specimens that test positive for influenza A viruses, we can detect unusual increases in influenza activity, which may indicate the early spread of novel influenza A viruses, including H5N1,” the CDC reported.

The CDC’s new tool aims to bolster surveillance of bird flu cases at the national, state, and local levels. Currently, the agency is monitoring 260 individuals who have been exposed to dairy cows infected with H5N1. As of the week ending May 10, there were no signs of unusual flu activity in people, including the H5N1 virus, according to the CDC’s surveillance system.

The first human case of bird flu in the U.S. was reported in 2022 following exposure to infected poultry, with a second case reported this year in Texas after contact with infected dairy cattle. The CDC has been testing wastewater from sewers to detect virus mutations that could enhance human transmission.

For the week ending May 4, 189 wastewater sampling sites across the U.S. exhibited higher-than-average levels of influenza A, requiring further analysis. Saline County, Kansas, showed particularly high levels. The CDC is closely monitoring these sites to determine potential contributing factors, including whether the elevated levels are associated with human illness.

However, the CDC cautioned that current wastewater monitoring methods cannot distinguish between subtypes of influenza A, meaning bird flu cannot be specifically identified this way. Additionally, wastewater testing cannot ascertain whether the influenza A virus originated from humans, animals, or animal products like milk.

“Efforts to monitor influenza A virus activity using wastewater data are likely to evolve as the methodologies and interpretation are evaluated and refined,” the CDC noted.

Bird flu has recently spread to dairy cows in the U.S., affecting 42 cattle herds in nine states. To contain the virus, the federal government has increased financial aid to dairy farms and enhanced testing for dairy workers and cattle. Impacted farms will receive an additional $28,000 for testing, protective gear for workers, veterinary bills, and compensation for lost milk production over the next four months.

The U.S. Department of Health and Human Services will allocate $101 million for testing and prevention efforts, while the CDC will invest $93 million in expanding virus testing and monitoring.

Despite these efforts, the risk to the general public remains low. The larger concern is the potential evolution of the virus to become easily transmissible among humans. Bird flu is considered more dangerous than the seasonal flu because it’s a new strain to humans and likely highly contagious.

“There’s no current evidence of sustained human-to-human transmission,” said Dr. Raj Panjabi of Harvard Medical School and former senior director for global health security and biodefense on the U.S. National Security Council. “Now is the time to increase investments in public health, focusing on prevention, protection, and preparedness.”

Federal officials have confirmed that the commercial milk supply, as well as milk-based products like cottage cheese and sour cream, are safe. However, agencies like the CDC, FDA, and USDA warn consumers against drinking unpasteurized milk, which may contain the virus. Pasteurization has been proven to kill the bird flu virus.

Should bird flu begin to spread from person to person, vaccines and antivirals are expected to be available, officials stated.