The Centers for Disease Control and Prevention (CDC) has reported the first case of “severe” avian influenza, popularly known as bird flu, just weeks after a child in California contracted the virus.

On Friday, the CDC announced that a person from Louisiana tested positive for avian influenza A virus, H5N1, after coming into contact with sick and deceased birds in a backyard flock. This patient was hospitalized, marking the first “severe” case of bird flu in humans in the United States.

“There is an ongoing investigation into how the Louisiana infection occurred. It has been confirmed that the patient had contact with sick and dead birds in backyard settings,” said the CDC. “This marks the first instance of H5N1 bird flu in the U.S. connected to backyard poultry.”

This new case arrives shortly after the first bird flu infection was confirmed in a child in California. As of this year, 61 infections have been reported across the U.S. according to the CDC.

What is bird flu?

Bird flu, or avian influenza, is a virus that can occasionally transfer from infected animals, primarily birds and some other species, to humans, the Cleveland Clinic explains. This virus mainly targets birds.

There are several subtypes of bird flu, but the H5 subtypes of influenza A are the most frequently observed.

The most prevalent types of avian influenza include:

• Influenza A(H5N1)
• Influenza A(H7N9)

Where have human infections occurred in the US?

Which animals are prone to infection?

Poultry are the primary carriers of avian influenza, as reported by the CDC, with about 123 million poultry impacted since 2022 across the nation.

Furthermore, since March 2024, over 700 dairy cow herds across 16 states have also been reported as infected.

Zoo animals infected in Phoenix

Several animals from the Wildlife World Zoo and Aquarium near Phoenix, including two big cats (a cheetah and a mountain lion) and three large birds (a swamphen, a kookaburra, and an Indian goose), have died or become infected due to bird flu exposure, according to previous reports from YSL News.

The sick animals were taken to the Arizona Department of Agriculture for examination, confirming they were likely exposed to avian influenza.

Who is at greatest risk?

Individuals most likely to catch bird flu are those who work with poultry, waterfowl, and dairy cows, according to the Cleveland Clinic. However, the CDC notes that the spread of the virus between people is extremely rare.

While human cases have been noted, the overall risk to the general public remains low, the CDC states.

How does bird flu spread?

A person can contract the virus by touching contaminated surfaces and then their face, particularly their eyes, nose, or mouth, according to the CDC. The virus can also spread through contact with infected live or dead animals.

Additionally, handling raw or unpasteurized dairy products from infected animals can lead to infection.

What are the symptoms of bird flu?

Symptoms of bird flu can vary significantly, resulting in either mild illness or severe disease leading to death, according to the CDC.

The following symptoms may appear, as listed by the Cleveland Clinic and CDC:

• Pink eye
• Fever
• Fatigue
• Cough
• Muscle aches
• Sore throat
• Nausea
• Vomiting
• Diarrhea
• Stuffy or runny nose
• Shortness of breath or difficulty breathing
• Headaches
• Pneumonia that requires hospitalization

How to prevent infection

To reduce the risk of contracting avian influenza, the CDC advises the following precautions:

• Stay away from sick or dead animals, especially wild birds and poultry.
• If you must interact with dead animals, ensure that you wear appropriate personal protective equipment (PPE), which should be provided by your employer at no charge.