Bird flu
DEFINITION
Bird flu is caused by a type of influenza virus that rarely infects humans. More than a dozen types of bird flu have been identified, including the two strains that have most recently infected humans — H5N1 and H7N9. When bird flu does strike humans, it can be deadly.
In recent years, outbreaks of bird flu have occurred in Asia, Africa and parts of Europe. Most people who have developed symptoms of bird flu have had close contact with sick birds. In a few cases, bird flu has passed from one person to another.
Health officials worry that a global outbreak could occur if a bird flu virus mutates into a form that transmits more easily from person to person. Researchers are working on vaccines to help protect people from bird flu.
CAUSES
Bird flu occurs naturally in wild waterfowl and can spread into domestic poultry, such as chickens, turkeys, ducks and geese. The disease is transmitted via contact with an infected bird’s feces, or secretions from its nose, mouth or eyes.
Open-air markets, where eggs and birds are sold in crowded and unsanitary conditions, are hotbeds of infection and can spread the disease into the wider community.
Undercooked poultry meat or eggs from infected birds can transmit bird flu. Poultry meat is safe to eat if it’s been cooked to an internal temperature of 165 F (74 C). Eggs should be cooked until the yolks and whites are firm.
SYMPTOMS
Signs and symptoms of bird flu may begin within two to eight days of infection, depending on the type. In most cases, they resemble those of conventional influenza, including:
- Cough
- Fever
- Sore throat
- Muscle aches
- Headache
- Shortness of breath
- Some people also experience nausea, vomiting or diarrhea. And in a few cases, a mild eye infection (conjunctivitis) is the only indication of the disease.
When to see a doctor
See your doctor immediately if you develop a fever, cough and body aches and have recently traveled to a part of the world where bird flu occurs. Be sure to let your doctor know if you visited any farms or open-air markets.
