Table 2.
Frequencies of genes in viruses selected through classical reassortment in our retrospective study of potential vaccine seed strains from 2003 to 2009 and in reassortant viruses from 1968 to 2009 reported in the literature
| Source of reassortment events | Viral subtype | No. of times gene originated from seasonal parent/total no. of reassortants |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| PB2 | PB1 | PA | HA | NP | NA | M | NS | ||
| Analyzed in this study | H3N2 | 1/15 | 8/16 | 2/16 | 16/16 | 0/16 | 16/16 | 0/16 | 2/16 |
| H1N1 | 0/5 | 3/5 | 0/5 | 5/5 | 0/5 | 5/5 | 0/5 | 0/5 | |
| Reported in the literaturea | H3N2 | 13/92 | 41/92 | 11/92 | 92/92 | 19/92 | 91/92 | 4/92 | 9/92 |
| H1N1 | 1/24 | 15/24 | 1/24 | 24/24 | 3/24 | 24/24 | 0/24 | 1/24 | |
| Combined totalb | H3N2 | 14/107 | 49/108 | 13/108 | 108/108 | 19/108 | 107/108 | 4/108 | 11/108 |
| H1N1 | 1/29 | 18/29 | 1/29 | 29/29 | 3/29 | 29/29 | 0/29 | 1/29 | |
a
The reassortant viruses analyzed from the literature were collated from references 11–14, 22, and 23.
b
Combined data from this and previously published studies.