Signs and Symptoms of Bird Flu in People
Key points
- Most human cases of bird flu, caused by avian influenza A(H5) virus, in the United States have been mild, so far, and most were in people who had known exposure to sick or infected animals.
- The severity of illness associated with bird flu has ranged from mild to severe, including death.
- The reported signs and symptoms of bird flu in humans have varied. Eye redness has been the predominant symptom among recent U.S. cases of avian influenza A(H5) virus infection. Respiratory symptoms and fever were also reported.
- The possibility of human infections with avian influenza virus that result in severe illness remains and underscores the importance of ongoing prevention and surveillance efforts.
Mild symptoms
Mild signs and symptoms of bird flu in people may include:
- eye redness and irritation (conjunctivitis)
- mild fever (temperature of 100ºF [37.8ºC] or greater) or feeling feverish*,
- cough
- sore throat
- runny or stuff nose
- muscle or body aches
- headaches
- fatigue
Eye redness has been the predominant symptom among recent U.S. cases of avian influenza A(H5) virus infection.
Less common symptoms include diarrhea, nausea, or vomiting.
*Fever may not always be present
Signs and Symptoms of Moderate to Severe Disease
Signs and symptoms of moderate to severe disease from bird flu in people may include:
- high fever or other symptoms listed above that limit or prevent usual activity
- shortness of breath or difficulty breathing
- altered consciousness
- seizures
Complications
Complications of bird flu can include but are not limited to:
- pneumonia,
- respiratory failure,
- acute respiratory distress syndrome,
- acute kidney injury
- multi-organ failure (respiratory and kidney failure),
- sepsis, septic shock
- and inflammation of the brain (meningoencephalitis)
Timing
Onset of Symptoms
The time from when a person is exposed and infected with avian influenza A(H5) viruses to when respiratory symptoms begin is about three days but can range from about 2 to 7 days. However, eye symptoms such as redness and irritation can occur one to two days after exposure and infection with an avian influenza A(H5) virus.
Period when people are contagious
- The period of contagiousness for person with mild illness due to bird flu is not well understood but thought to be similar to seasonal flu.
- People are thought to be most contagious during the first few days of their illness.
- People with severe disease (e.g., pneumonia) requiring hospitalization may have high levels of virus in the lower respiratory tract and may be contagious for several weeks.
How long bird flu illness lasts
Bird flu usually lasts a few days to less than two weeks, but how long symptoms last can vary by person. People who are severely ill (for example, intubated for severe pneumonia and respiratory failure) may be sick for several weeks.
When there are no symptoms
Some people who have had bird flu in the United States have reported no symptoms. It is not currently known how common this is. People who do not have symptoms can still be contagious to others.
Bird Flu Has Been Found In All 50 States—Health Experts Recommend Taking These Safety Precautions
source-Yahoo.1/9/2025
Bird Flu: Can We Still Eat Eggs & Poultry? Kwangmoozaa – Getty Images
The threat of avian flu has dominated public health discourse as cases become increasingly more widespread and severe. H5N1, a highly pathogenic strain, was present in several continents as early as 1996. Since reaching North America in late 2021, this strain has impacted wild animals, commercial livestock, and humans. Just this week, the first fatal human case of H5N1 was reported in Louisiana—someone over 65 who was exposed to a backyard flock of birds and wild birds.
The US Centers for Disease Control and Prevention (CDC) identified that the nation’s first 46 cases in 2024 were all mild and, save for one, all caused by exposure to infected animals. Health experts still maintain that the current public health risk is low, but consumers are understandably growing concerned about how this strain of avian flu will impact the food we eat.
The U.S. Department of Agriculture (USDA) announced in March 2024 that H5N1 began impacting dairy cattle in a few states. Since then, the outbreaks among cattle have continued across 16 states and spread to dozens of humans, prompting California Governor Gavin Newsom to declare a state of emergency. The prominence of H5N1 is even more evident among commercial poultry, where cases have been identified in all 50 states.
But how will all of this impact the eggs and poultry we eat? is it, in fact, safe to keep eating these products? We’re breaking down everything we know so far.Grace Cary – Getty Images
H5N1 has presented a hindrance when it comes to the commercial dairy and livestock industry, but not in a way that will necessarily get you sick. “We have already seen milk infected with H5N1, but pasteurization kills the virus. We have not found it in beef, chicken or eggs,” says Brian Labus, PhD, MPH, REHS, Assistant Professor at University of Nevada Las Vegas’s School of Public Health.
“The likelihood of H5N1 being transmitted in poultry products is extremely low as the onset of symptoms appear rapidly in poultry, especially turkeys, and the birds quickly succumb to the virus,” says Mitzi Baum, CEO of Stop Foodborne Illness. The onset of H5N1 is so fast that Labus says that infected birds do not have enough time to lay eggs before the symptoms become fatal.
In addition, several federal and industry guidelines are in place to further reduce the risk of H5N1 entering our food supply. “The likelihood that eggs from infected poultry are in the retail market is low, due to safeguards in place, which include testing of flocks and federal inspection programs,” says Dr. Mickey Rubin, Vice President of Research for The American Egg Board. “Once a commercial poultry farm is identified as HPAI positive, the farm is placed under quarantine, and all movement of eggs and birds immediately stops. This is required and enforced by state veterinarians working collaboratively with USDA.”
Rubin also notes that egg farmers dealing with an avian flu outbreak cannot resume normal operations without thorough cleaning, disinfecting, testing, and approval from the USDA and the state government. The loss in production helps prevent infected products from reaching the food supply. It also puts a strain on the supply chain, which may increase egg and poultry prices for the consumer.
Can We Still Eat Eggs & Poultry?
Brett Holmes Photography – Getty Images
When it comes to avian flu risk levels, buying eggs and poultry from the supermarket is on the lower end of the spectrum. The CDC argues that there is no evidence that food will transmit H5N1—as long as it’s cooked and handled properly.
“Although H5N1 can potentially be found in our food, influenza isn’t really a foodborne disease. You have to breathe it in to get sick, not eat it,” Labus explains. “There is a much greater risk of being infected with common foodborne pathogens like Salmonella.”
Health experts advise fully cooking your eggs and poultry to an internal temperature of 165°F to kill bacteria and viruses, including this strain of avian influenza. Thoroughly cooking your chicken is something most home cooks are familiar with doing, but the increased precautions may affect how you consume eggs. Soft, runny, and undercooked eggs don’t reach a high enough temperature to stave away pathogens, which presents the risk of transmission. The safest way to eat eggs is to cook them all the way, meaning both the white and yolk are firm.
If you’re not ready to give up on runny eggs, Baum suggests buying pasteurized shell eggs that can reduce the risk of transmission. It’s also advised that you use these eggs, or pasteurized egg products, when making recipes that don’t cook eggs all the way through. Examples include salad dressings and homemade ice cream.