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- Patient Comments: Bird Flu - Experience
- Patient Comments: Bird Flu - Symptoms
- Bird flu (avian flu) facts
- What is bird flu?
- What causes bird flu?
- What are risk factors for bird flu?
- What are bird flu symptoms and signs?
- How do physicians diagnose bird flu?
- What is the treatment for bird flu?
- What are the complications of bird flu?
- What is the prognosis of bird flu?
- Can bird flu be prevented with a vaccine?
- Where can people find more information about bird flu?
What are risk factors for bird flu?
Humans may get bird flu from contact with infected birds (chickens, for example) or their infected droppings and secretions. Risk factors include caring for sick birds, killing sick birds, and preparing sick birds for consumption. Despite the large number of people who have contact with poultry every day in the world, human cases of bird flu remain rare. This highlights how difficult it is for the bird flu virus to infect human cells, but mutations like antigenic shifts may reduce such difficulties. The H1N1 pandemic that started in Mexico is an example of such a mutation (swine flu to human flu).
Although direct contact with sick poultry poses the highest risk for bird flu, indirect exposure to bird feces or other materials such as bird eggs is also a risk. Contact with unwashed eggs from sick birds or water contaminated by poultry feces poses a potential risk of disease.
Human-to-human spread has occurred in isolated cases. Thus, caring for a person infected with bird flu is also a risk factor for the disease. There is a theoretical risk in laboratory workers who handle the avian flu virus. One alleged incident in 2009 occurred when a company inadvertently sent live avian flu virus samples to research laboratories, which subsequently were used to vaccinate ferrets. The contaminated vaccine did not result in any human infections.
What are bird flu symptoms and signs?
Symptoms occur approximately two to eight days after exposure, on average. Infected people experience typical flu-like symptoms that may include
- fever (above 38 C or 100.4 F),
- cough (usually dry or nonproductive of sputum),
- sore throat,
- muscle aches,
- joint pain,
- nasal secretions (runny nose),
- eye infections.
Children get similar symptoms. This viral infection can progress to pneumonia and even respiratory failure. Bird flu causes a very aggressive form of pneumonia (acute respiratory distress syndrome or ARDS) that is often fatal.