Update: influenza activity--worldwide, 1994.

From October 1993 through August 1994, influenza activity occurred at moderate to moderately severe levels worldwide. Influenza A(H3N2) viruses predominated during the 1993-94 season, but influenza B viruses also were isolated from persons with sporadic illness and from outbreak-associated cases. Cocirculation of influenza A(H3N2) and influenza B viruses is continuing throughout the world; however, the isolation of influenza A(H1N1) viruses has been extremely rare (1). This report summarizes influenza activity worldwide from March through August 1994.