Fast-Evolving Retroviruses

Retroviruses have mutation rate of 2 × 10 -5 mutations per nucleotide per replication cycle.

~ Louis M. Mansky (1961 age:56)

Retroviruses don’t have an error-correction mechanism to fix mutations. Bacteria do. So for example E. coli has a mutation rate of only 10 -10 . E. coli as 200,000 times as precise.