Genetic sequencing shows a new sub type of influenza A (H1N1) virus with segments from four influenza viruses: North American Swine, North American Avian, Human Influenza and Eurasian Swine.
The majority of these cases have occurred in otherwise healthy young adults.
The transmission is by droplet infection and fomites.
From 1 day before to 7 days after the onset of symptoms. If illness persist for more than 7 days, chances of communicability may persist till resolution of illness. Children may spread the virus for a longer period.
There is substantial gap in the epidemiology of the novel virus which got re-assorted from swine influenza.