Which influenza strain was isolated in 1989 spreading to many other countries?
In 1989, epidemic - the reappearance of swine HINI virus Influenza can occur sporadically, as epidemics or pandemics In 2009, H1N1 Epidemic occurred in Mexico-recent Ref: Baveja 5th ed Pg: 468
H2N2
H1N1
H3N2
H5N1
Virology