الفهرس 
Chapter I : IntroductionOnly 14 pages are availabe for public view
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Abstract
Avian influenza is an infectious disease by influenza type Astrain occurs naturally among birds. Wild birds worldwide carry the viruses in their intestines, but usually do not get sick. However, avian influenza is very contagious among birds and can make some domesticated birds including chickens, ducks, andturkeys, very sick and kill them (De Jong, 2006).
Infected birds shed influenza virus in their saliva, nasal secretions, susceptible birds become infected when they have contact with contaminated secretions or excretions or with surfaces that are contaminated with secretions or excretions from infected birds. Domesticated birds may become infected with avian influenza virus through direct contact with infected waterfowl or other infected poultry, or through contact with surfaces such as dirt or cages or materials such as water or feed that have been contaminated with the virus (CDC, 2007). Infection with avian influenza viruses in domestic poultry causes forms of disease that are distinguished by low and high extremes of irulence. The “low pathogenic” form may go undetected and usually causes only mild symptoms (such as ruffled feathers and a DROP in egg production). However, the highly pathogenic form spreads more rapidly through flocks of poultry. This form may cause disease that affects multiple internal organs
and has a mortality rate that can reach often within 48 hours 2007).
Close contact with dead or sick birds is the principal source of human
infection with H5N1 virus .Most human cases had occurred in rural or peri
urban areas where many household keep small poultry flocks, which often roam freely (Bridges et al., 2003)
Human-to-human transmission of the avian influenza rarely reported,
However, experts warn an occurrence of ‘‘mutant avian influenza’’, which
can easily spread among humans, because the avian influenza is already endemic, particularly in Asian poultry, and it is evolving in domestic and wild birds, pigs and humans. Outbreak of such mutant avian influenza in the human world may have devastating consequences, which are comparable these for the 1918 ‘‘Spanish influenza’’ (Shingo,et al.2008).
Egypt is the third country to report laboratory- confirmed human cases.
The total number of confirmed human cases of avian influenza in Egypt until April 2012 reached 166 cases with 59 deaths (WHO, 2012).
Prevention of such disease can be attained at three levels: Primary prevention; which includes efforts to reduce the incidence of disease through health promotion and education; secondary prevention; includes seek to reduce disease prevalence and disease morbidity through early diagnosis and
treatment, and tertiary prevention; as tries to reduce complications and disabilities of disease (Stanhope and Lancaster, 2002).
prevalence and risk factors for zoonotic influenza infection is necessary to improve public health measures and pandemic preparedness. This information will improve the ability to plan activities and inform vaccination and antiviral policies.