Which influenza strain was isolated in 1989 spreading to many other countries?: (A) H2N2, (B) H1N1, (C) H3N2, (D) H5N1
Answer is B. 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