CDC Tells States to Prepare for Bird Flu, Says Risk to Humans Remains Low

The virus has been found in 11 dairy herds, and a Texas farm worker tested positive more than a week ago, prompting advisories.

The Centers for Disease Control and Prevention (CDC) headquarters in Atlanta on April 23, 2020. Tami Chappell/AFP via Getty Images

The risk of bird flu to humans is low right now, but state health officials need to be ready to respond, the U.S. Centers for Disease Control and Prevention (CDC) said in an update issued on April 8.

In a readout of a call held on April 5, the CDC said that it asked for states to be “prepared to quickly respond” to provide treatment and test potentially impacted farm workers after dairy cows had tested positive for H5N1 in recent days.

A dairy worker in Texas was diagnosed with the virus more than a week ago, officials said, prompting a slew of advisories.

The CDC recommended that state officials “engage” local agriculture officials and veterinarians to have updated “operational plans to respond to avian influenza” and that state officials should test for and quickly treat bird flu if cases are confirmed among farm workers.

The Texas farm worker was reported to be infected on April 1, making it the second case of the H5N1 strain of avian influenza identified in a person in the United States. One human case was reported in 2022 in Colorado.

The avian influenza also has spread to dairy cows in Texas, Kansas, New Mexico, Michigan, and Idaho, according to the U.S. Department of Agriculture, in what appears to be the first time the pathogen has infected cattle.

This past week, the CDC said the infection does not change the risk assessment for the public from H5N1 bird flu, which it said was low. The Texas patient’s only symptom was eye inflammation, according to the state health department.

Health Alert

Over the weekend, the agency issued a “health alert network” advisory to healthcare providers, state health departments, and the public after the flu case was confirmed in Texas.

The CDC’s “updated recommendations” include “instructions for infection prevention and control measures, using personal protective equipment (PPE), testing, antiviral treatment, patient investigations, monitoring of exposed persons” such as individuals who have been “exposed to sick or dead wild and domesticated animals and livestock with suspected or confirmed infection” with avian influenza.

Individuals with a confirmed case or with bird flu-like symptoms should be isolated, given antiviral treatment, and be isolated from household members, according to the notice.

“People with job-related or recreational exposures to infected birds, cattle, or other animals are at higher risk of infection and should take appropriate precautions,” the advisory said, while noting that the risk to the public is low.

People who own backyard flocks of chickens and other birds, poultry and livestock farmers and workers, and veterinarians should wear “recommended PPE” such as N95 masks, eye protection, and gloves, the CDC said. Washing hands is also advised after any contact with livestock and birds.

CDC Director Dr. Mandy Cohen told ABC News this past week that federal authorities have been prepared for an avian influenza outbreak for the past two decades.

“These are the things that reassure me: 20 years of preparation, no genetic changes to this virus, no human-to-human spread, and nothing in the virus in terms of adaptations that would make us think it is more adaptive to human spread,” she said.

Milk Supply Safe, USDA Says

There are 11 dairy herds with confirmed positive cases, the U.S. Department of Agriculture has said. Seven farms in Texas, two in Kansas, one in New Mexico, and one in Michigan are impacted.

The USDA said this past week that the nation’s milk supply is safe. Milk from sick cows is being diverted and destroyed so it does not enter the food supply. Pasteurization is required for milk entering interstate commerce, a process that kills bacteria and viruses such as flu.

In an update on April 8, the USDA said it did not see the need to cull dairy herds since infected cows were being isolated and reportedly recovering.

Avian flu has reached new corners of the globe in recent years, spread by wild birds. Since 2022, 82 million U.S. chickens, turkeys, and other birds have been culled.

The virus is fatal to poultry but has been less severe in mammals. This year, H5N1 was also found in a goat in Minnesota on a farm where poultry tested positive.

About 900 human cases of avian influenza have been identified since 2003, says the UN’s World Health Organization. About half of the infected people have died, the agency said, adding that nearly all of the human cases were linked to contact with infected birds or contaminated areas.

Reuters contributed to this report.