Oligonucleotide mapping of viral ribonucleic acid as an aid in identifying laboratory contaminants of influenza virus.

Influenza viruses that were suspected to be laboratory contaminants of clinical specimens because they had antigenic properties identical to standard laboratory strains were examined by T1 oligonucleotide mapping of virion ribonucleic acid. For the three instances reported herein involving thirteen viruses, it was concluded that laboratory contamination had occurred, since in each instance, a standard laboratory strain that had been used in the clinical laboratory before the isolation, had an oligonucleotide map that was either identical to or very similar to those of the "isolates," there was no evidence of spread of these viruses, and in cases where serum samples were available, no serologic evidence existed of infection by these virus strains.