Context: Indian scientists have detected the country’s first case of infection with a rare variant of the virus- H9N2- that causes avian influenza, or bird flu.

About H9N2:

H9N2 is a subtype of the influenza A virus, which causes human influenza as well as bird flu.

The H9N2 subtype was isolated for the first time in Wisconsin, US in 1966 from turkey flocks.

H9N2 viruses are found worldwide in wild birds and are endemic in poultry in many areas.

Threats and concerns:

H9N2 viruses could potentially play a major role in the emergence of the next influenza pandemic.

According to the World Health Organization (WHO), with avian influenza viruses circulating in poultry, there is a risk for sporadic infection and small clusters of human cases due to exposure to infected poultry or contaminated environments. Therefore, sporadic human cases are not unexpected.