ABSTRACT
This chapter deals with the replication of influenza viruses, concentrating particularly on the functional activity of the genetic constituents of the virus and the way in which the genome is reproduced. It considers the replication of influenza viruses, with emphasis on transcription of the genome into Messenger Ribonucleic Acid (RNA). The chapter examines the similarities and differences between the replication of influenza and parainfluenza viruses. The parainfluenza virus group consists of parainfluenza viruses 1 to 4, simian virus 5, mumps, and Newcastle disease virus. There is a general morphological similarity between the influenza and parainfluenza viruses, although the latter are much larger. Like the influenza viruses, the neuraminidase-containing parainfluenza viruses grow to highest titer in chick allantoic cells and are released into the allantoic fluid. The molecular aspects of RNA transcription and replication by parainfluenza viruses have a great deal in common with those observed for influenza viruses. The replication of parainfluenza virus RNA is a mystery.
