Infection with avian influenza viruses among poultry causes two main forms of disease, which are distinguished by low and high extremes of virulence. The "low pathogenic" form may go undetected and causes only mild symptoms. The "highly pathogenic" form spreads more rapidly through flocks and may cause diseases that affects multiple internal organs. Though avian influenza does not typically infect people, they may become infected as a result of direct or close contact with poultry or contaminated surfaces. Avian influenza has to be confirmed in humans by a laboratory test. The H5N1 strain of the virus has caused the largest number of severe disease and death in humans. The spread of H5N1 has not continued to be passed by one person because transmission between people occurs very rarely.
Avian Flu Symptoms in Birds:
In the low pathogenic form:
1) Respiratory Problems - trouble breathing, sneezing, and coughing
2) Reduced egg production or soft shell production
3) Ruffled feathers
4) Swelling of the eyes, combs, and wattle
5) Loss of appetite
6) Diarrhea
7) Dehydration
The highly pathogenic H5N1 strain can cause very rapid death in birds. This form has a mortality rate that can reach 90 - 100% within 48 hours. In many cases the birds can die before there are any obvious clinical symptoms. Sick birds will often appear to be in a coma state of mind with their heads touching the ground.
Avian Flu symptoms in humans:
The low pathogenic form includes the typical symptoms of conventional influenza:
1) Cough
2) Fever
3) Sore Throat
4) Muscle Aches
5) Eye infections (conjunctivitis)
People with the more virulent type of the virus, H5N1,
can develop life-threatening complications:
1)Acute respiratory distress
2) Viral pneumonia
