Signs and Symptoms of Bird Flu

Bird flu, or avian influenza, is an illness humans can get from animals infected with avian influenza A viruses. There are several types of bird flu viruses, including the more common H5N1. Bird flu can be found in wild waterfowl like geese or human-owned poultry such as chickens and ducks. Sometimes, other animals, including dairy cows, can carry the virus.

It is rare for bird flu to spread to humans. However, you can acquire bird flu if you touch an infected animal's feces (poop) or bodily fluids and then touch your nose, mouth, or eyes. It's also possible to breathe in the virus. Usually, bird flu doesn't spread between people, but experts worry person-to-person transmission might become a problem someday.

Bird flu symptoms in humans can vary widely in severity. Some people might not get any symptoms. Other people can get mild symptoms, such as fever, sore throat, and eye redness. Severe symptoms like pneumonia are also possible. Symptoms may come on suddenly or gradually worsen over time. 

Common Symptoms

Often, bird flu symptoms are similar to those of the seasonal flu. This might include a group of upper-respiratory symptoms, which are symptoms that affect your nose, throat, and airways.

Fever

While it doesn't always occur, a fever is often one of the initial signs of bird flu. A fever is a body temperature above the normal range. With bird flu, the fever is typically around 100 degrees or higher. You may experience chills with the fever. 

Sore Throat

Pain, scratchiness, or irritation in the throat is a common symptom of bird flu and may occur before other symptoms. A sore throat can range from mild to severe. It may worsen when talking or swallowing, sometimes making it uncomfortable to eat or drink.

Upper Respiratory Symptoms

You might experience a runny nose, cough, or congestion. In more severe cases of bird flu, you may have shortness of breath. This can indicate pneumonia, a lung infection, or other serious breathing problem that requires immediate medical attention.

Aches, Fatigue, and Malaise

If you become infected with bird flu, you may have joint or muscle aches, fatigue, or malaise. Fatigue is extreme tiredness or lack of energy. Malaise is a general feeling of being unwell. These symptoms often occur with a sore throat, fever, and cough. 

Pink Eye (Conjunctivitis)

Pink eye (conjunctivitis) is inflammation of the conjunctiva, a clear layer of tissue that lines the eyelids and covers the white of the eye. Symptoms of pink eye can include:

• Eye redness 
• Burning or itching of the eyes 
• Excess tearing or discharge (fluid) from the eyes
• Small bumps in the inner eyelids
• Swelling of the eyes
• Swollen glands near the ears

Less Common Symptoms

While not as common as upper-respiratory symptoms, diarrhea, nausea, and vomiting can occur with bird flu.

Diarrhea is loose or watery bowel movements that happen three or more times a day. You might also experience cramps or pain in the abdomen or urgently need to go to the bathroom.

Nausea is a feeling of stomach unease, as though you might vomit. You might vomit.

Rare Symptoms

In rare cases, bird flu can cause swelling or irritation in the brain, spinal cord, or nerves. This may cause dizziness, problems with concentration, or headaches. In severe cases, you could have seizures, where your body shakes uncontrollably due to a burst of electrical activity in the brain, or fall into a coma (when you can't wake up).

Symptoms in Birds

Knowing the signs of bird flu in birds themselves can help you determine whether you might have been exposed to and contracted the virus. Some birds with bird flu may now show any signs of illness. When birds do have symptoms, they may include:

• Behavioral changes
• Bluish skin color
• Difficulty breathing
• Diarrhea
• Excess tear production
• Leg bleeding
• Less egg production
• Loss of appetite
• Rapidly progressive illness that causes death
• Ruffled feathers
• Head and face swelling

When to Contact a Healthcare Provider

If you suspect or know you've come into contact with an infected animal, contact your local health department. They may check in with you over the next week or so to see if you've developed any symptoms.

Contact a healthcare provider if you have symptoms of bird flu—especially if you might have been exposed to an infected animal. They might perform diagnostic testing, such as a throat or nasal swab. These tests are more accurate in the first few days of illness.

You'll want to get immediate care if you are experiencing any severe symptoms like seizures or trouble breathing. It’s also important to seek emergency care if you have signs of severe dehydration (when your body doesn’t have enough water to function correctly). Signs of severe dehydration include:

• Confusion or irritability
• Dark urine or inability to produce urine 
• Dizziness or lightheadedness
• Extreme thirst
• Rapid breathing 
• Rapid heartbeat
• Sunken eyes
• Dry mouth
• Weakness

A Quick Review 

Bird flu is a viral infection that birds can have and spread. Rarely, humans can contract bird flu. When bird flu occurs in humans, symptoms can range in severity. Some people might not have any symptoms. If there are symptoms, they usually resemble those of the seasonal flu, such as stuffy nose, cough, sore throat, body aches, eye irritation, fever, and fatigue.

Less commonly, bird flu can cause nausea, vomiting, or diarrhea. In more severe cases, the infection can lead to breathing difficulties and seizures. Seek medical attention if symptoms persist or worsen.