Measuring PFU Has the Advantage Over Direct Virus Count Methods

Question

Measuring PFU has the advantage over direct virus count methods because it informs on:
A)viral structure
B)infectivity
C)enveloped versus non-enveloped anatomy
D)the burst size
E)chromosomal structure

Accepted Answer

PFU (plaque-forming units) is a measure of the number of infectious viral particles. Unlike direct virus count methods, which also count non-infectious or defective viral particles, PFU only counts particles capable of forming visible plaques. Therefore, measuring PFU informs on infectivity, which is a crucial factor in understanding viral replication and virulence. The other choices (A, C, D, E) may provide useful information, but they are not directly related to the advantages of measuring PFU over direct virus count methods.