Avian influenza, also known as bird flu, is a disease that primarily affects birds and it is caused by a virus of the Orthomyxoviridae family.
According to its subtype, it may be classified as high or low pathogenicity, presenting different symptoms in infected birds. The Low Pathogenic Avian Influenza Virus (LPAIV) can cause a mild illness, often unnoticed or without any symptoms. The Highly Pathogenic Avian Influenza Virus (HPAIV) caused mainly by subtypes (H5 and H7) of type A, causes a serious illness in birds that can spread rapidly, resulting in high death rates in different species of birds.
Most of the influenza viruses circulating in birds are not zoonotic. However, some HPAI strains have the ability to infect humans, posing a threat to public health. The main risk factor is the direct or indirect exposure to infected animals or environments and surfaces contaminated by feces.
:: Background Information
The International Health Regulations (2005), establish a new framework for the notification, consultation and evaluation of avian influenza related events.
:: World Health Organization
:: Collaborating animal health organizations and initiatives
:: PAHO/WHO Resources
Regional Office for the Americas of the World Health Organization