Dr. Brechot’s Health Research & Care Blog

April 25th, 2023



Do we need to be concerned about avian flu?

Everyone has noticed that the prices of eggs and poultry have gone up. One reason is the continued spread of avian flu. So, what is avian flu? Should we be worried?

What is avian flu?

Avian influenza, also known as bird flu, is a highly contagious viral infection that affects both domestic and wild birds. There are several strains of bird flu, among which H5N1 and H7N9 are more worrisome due to the possibility of transmission from birds to humans. While this rarely happens, H5N1 is a highly pathogenic virus. Since 1997, outbreaks of this strain and a few infections in humans have occurred in Asia, Africa, and Europe. H5N1 can infect mammals that eat the dead bird cadavers. Such infections could increase the risk of mutations in the virus that could make it more transmissible to humans. Recently, there has been a spillover of the H5N1 virus into harbor and gray seals in New England.  You can read more about the risk of future mutations in the H5N1 strain of virus in this post by the Global Virus Network.

While very rare, it is possible for people who come into close contact with infected birds, bird saliva or feces to get infected. According to the Centers for Disease Control and Prevention’s latest update on H5N1, 58 million poultry birds in more than 46 states been infected. So far, one human case has been reported in the United States. Between December 2022 and March 2023, 24 countries in Europe reported H5N1 cases in domestic and wild birds.

The symptoms of avian flu

The symptoms of avian flu vary. Infected birds can experience diarrhea, respiratory problems, and a sudden drop in egg production. In severe cases, they may die.

Most people infected with bird flu will experience very mild symptoms, such as  fever, cough, vomiting,  sore throat, and diarrhea, according to the World Health Organization. A few patients may develop more severe symptoms, such as pneumonia, difficulty breathing, respiratory failure, and even death. The fatality rate for humans from infection with H5N1 or H7N9 is much higher than that of seasonal flu infection.

Prevention and treatment

Preventing bird flu is crucial. While most people are at low risk of contracting bird flu, people who handle birds should take precautions.  Proper measurements include isolating infected birds, sterilizing equipment, monitoring bird populations for signs of disease, wearing protective gear, and washing hands frequently. If you suspect you are sick, please seek medical attention immediately.

There are also vaccines for birds, although they are not always effective.

In humans, antiviral drugs such as neuraminidase inhibitors (oseltamivir, zanamivir) can be used to treat bird flu. They are most effective when taken within 48 hours of the onset of symptoms.  Seasonal influenza vaccines do not fully protect against bird flu infection, but they do reduce the risk.

Although we have developed a deep understanding of how bird flu interacts with its host, we still have a long way to go to better understand the evolving bird flu and develop new antiviral drugs and vaccines to fight different strains of bird flu. Closely monitoring virus outbreaks is critical to prevent them from becoming the next pandemic.

Christian Brèchot, MD, PhD
Senior Associate Dean for Research in Global Affairs, USF Health Morsani College of Medicine
Associate Vice President for International Partnerships and Innovation, USF
Professor, Department of Internal Medicine
President, Global Virus Network



Linman Li, MBA, MPH, PMP, CPH
Director, USF- GVN Center
USF Health Morsani College of Medicine
Vice President, Global Virus Network