The Centers for Disease Control and Prevention on Wednesday reported the second human case of the bird flu associated with dairy cows.
The CDC said that the person who was diagnosed with bird flu works at a dairy farm where the H5N1 virus has been found in cows. A nasal swab from the worker tested negative but an eye swab that was sent to the CDC tested positive and indicated that they had an eye infection.
The worker only reported mild symptoms, according to The New York Times.
It is the second case since last month where an H5N1 infection in a human was reported. The other one was at a dairy farm in Texas and was the first case associated with an outbreak in dairy cows, the newspaper reported.
The name of the worker and the farm have not been released, according to the Times.
H5N1 has been confirmed in about 51 dairy herds in nine states as of Wednesday, according to the U.S. Agriculture Department, per The Associated Press. Fifteen of the 21 herds were found in Michigan.
H5N1 has been found in high levels of raw milk of infected cows, the AP reported. Officials say it is believed that pasteurized dairy items in grocery stores are safe. The pasteurizing process has heat treatment, which is believed to have killed the virus.
[ Bird flu sickens 1 in Texas after spreading to dairy cattle ]
Officials are working to understand how the virus is spreading. They added that the infections won’t endanger the commercial milk supply as dairies must destroy or divert milk from sick cows, and pasteurization has been shown to kill avian flu viruses.
Authorities urged healthcare providers to be aware of possible avian flu infections in people who have symptoms of the flu and a relevant exposure history. According to the Texas Department of State Health Services, signs of the avian flu can include:
- Fever (temperature of 100°F or greater) or feeling feverish or chills
- Cough
- Sore throat
- Runny or stuffy nose
- Headaches
- Fatigue
- Eye redness (conjunctivitis)
- Difficulty breathing/shortness of breath
- Diarrhea
- Nausea
- Vomiting
- Seizures
Conjunctivitis or pink eye has also been reported in some infections, authorities noted.
In 2022, officials said a poultry worker in Colorado who had direct exposure to birds believed to have been infected with the avian flu tested positive for the virus. They reported fatigue for a few days before they recovered, according to the CDC.