The greatest risk factor for bird flu seems to be contact with sick birds or with surfaces contaminated by their feathers, saliva or droppings.
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).
People with bird flu may develop life-threatening complications. The complications of bird flu are frequently dire and include:
- Shortness of breath or difficulty breathing,
- Acute respiratory distress syndrome (ARDS),
- Abdominal pain,
- Lung collapse,
- Altered mental status,
- Organ system failure, and
Routine tests for human influenza A will be positive in patients with bird flu but are not specific for the avian virus. If bird flu is suspected, the following tests will be carried out to establish whether you have the infection:
Samples of fluids from your nose or throat can be tested for evidence of bird flu virus. These samples must be taken within the first few days after symptoms appear. The virus can be detected in sputum by several methods, including culture or polymerase chain reaction (PCR). Cultures should be done in laboratories that have an appropriate biosafety certification. PCR detects nucleic acid from the influenza A virus. Specialized PCR testing is available in reference laboratories to identify avian strains; the CDC is a primary source for available tests for the newest strains of bird flu and can identify the specific type of virus (for example, H5N1 or H7N9).