Prevention of avian influenza epidemic: What policy should we choose?

Human-to-human transmission of the avian influenza has been extremely rarely reported, and is considered as limited, inefficient and unsustained. However, experts warn an occurrence of "mutant avian influenza", which can easily spread among humans, because the avian influenza is already endemic, in particular 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 with these for the 1918 "Spanish influenza". In this paper we develop a mathematical model for the spread of the mutant avian influenza, and explore the effectivity of the prevention policies, namely the elimination policy which increases the effective additional death rate of the infected birds and the quarantine policy which reduces the number of infective contacts.