Passenger virus
A passenger virus is a
tumours, but is not a contributing factor in causing the disease
.
Experimental demonstration of passenger status
Proving that a virus has no causative role can be difficult. Although none of the following signs is definitive, evidence that a virus found in diseased tissue might be passenger only rather than a causative agent includes:
- injection of the virus into healthy animals without causing disease;
- the absence of the virus at the earliest stages of the disease;
- curing the viral infection using antiviral drugs or vaccination with no effect on the course of the disease.
Examples
A well-established example is
AIDS.[6]