What to know about bird flu, from a UI infectious disease specialist
Bird flu is widespread in birds and has recently caused some outbreaks in poultry and cows in the United States.
To learn more, we talked to infectious disease specialist and epidemiologist Karen Brust, MD.
- Bird flu is widespread in wild birds worldwide and is causing outbreaks in poultry and U.S. dairy cows with recent human cases in U.S. dairy and poultry workers.
- The current public health risk is low.
- Anyone with work or recreational exposures to infected birds/poultry and cattle should take precautions.
What is bird flu?
Commonly known as bird flu, avian influenza is a disease caused by infection with avian influenza Type A viruses. These viruses naturally spread among wild aquatic birds worldwide and can infect poultry and other bird and animal species.
All 50 states currently have detected wild birds with bird flu, and outbreaks among poultry have occurred in 48 states. Thirteen states have seen outbreaks among 171 cattle herds on large-scale industrial farms. Just recently, a group of cases have been reported in the U.S. this year.
Does bird flu infect humans?
Not typically, no. Although bird flu doesn’t normally infect humans, it does have the potential to cross-over and we have seen occasional human infections with bird flu.
A total of 14 human cases have ever been reported in the U.S. as of Aug. 1. The first case we saw in the U.S. occurred in 2022. Recently in April, one case was reported in a dairy worker in Texas, two cases were found in Michigan dairy workers in May, and nine cases have been found in two separate farms in Colorado in July. The most recent cases have mild illness and have been offered antiviral medication.
What are the symptoms?
The effects of bird flu can range from mild flu-like upper respiratory symptoms or eye redness to severe illness such as pneumonia requiring hospitalization.
Symptoms include:
- Eye redness (conjunctivitis)
- Fever
- Cough
- Sore throat
- Runny or stuff nose
- Muscle or body aches
- Headaches
- Fatigue
- Shortness of breath or difficulty breathing
Sometimes we might see diarrhea, nausea, vomiting, or seizures caused by bird flu.
How does it spread?
Infection happens through exposure to saliva, mucus, or feces from infected animals.
Infections among people are rare because currently circulating viruses cannot easily bind to human receptors.
What are the preventative measures I can take?
Don’t touch wild birds and observe them only from a distance. This includes avoiding sick or dead domesticated poultry and cattle or surfaces contaminated by them.
If you plan to view livestock through work or recreation at a local fair, minimize direct contact by wearing gloves (if you plan to interact with the animal) and wash your hands with soap and water afterwards.
It’s safe to drink pasteurized milk and eat properly handled and cooked poultry and cattle products in the U.S. Cooking these products to an internal temperature of 165 degrees Fahrenheit kills bacteria and viruses, including bird flu viruses.
What is the treatment?
If you get sick after being in close contact with infected or potentially infected birds or other animals, you should contact a health care provider.
Antiviral drugs are the recommended treatment for patients infected with bird flu, and this treatment works best when started as soon as symptoms begin.
How do I know if I have bird flu?
Bird flu infection in people cannot be diagnosed by clinical signs and symptoms alone, we would have to use laboratory testing. Bird flu virus infection is usually diagnosed by collecting a swab from the upper respiratory tract (nasopharyngeal swab) of the sick person. Standard influenza A PCR testing will be positive in cases of bird flu but it will not identify the specific type of influenza A the patient has.
The spread of bird flu amongst wild birds is causing outbreaks in poultry and dairy cows in the U.S., but the risk to people is low. We all can do our part in containing the spread.
