What is the significance of a virus going from an animal host to a human host? Is this something we should all be seriously concerned about or media hype?
Our concern should reflect that of the experts who are seeking to deal with this possible pandemic. The World Health Organisation is the lead responding to the outbreak and they have currently declared a Phase 6. Influenza viruses are commonly circulating in the human and animal environment. Different strains can cause illness in humans, bird and pigs. Humans have some natural immunity to the common strains that are human-to -human influenza. Mixing of human and animal influenza viruses can lead to the development of changed viruses with the ability to cause infection and spread in the human population. There may be little or no immunity in the human population to these new viruses, enabling the infection to spread more easily and increase the affects of the infection on the host.
