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 is a passenger 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.
A well-established example is lactate dehydrogenase virus, which is often found in mouse tumours. GB virus C and Chandipura virus are possible examples in humans. It has also been suggested that a virus related to Alcelaphine herpesvirus 1 is a passenger virus that, unlike AHV1 itself, doesn't cause bovine malignant catarrhal fever. The discredited Duesberg hypothesis posits that HIV is a passenger virus in the etiology of AIDS.
- Mongini PK, Rosenberg LT. (1976) Inhibition of lymphocyte trapping by a passenger virus in murine ascitic tumors: characterization of lactic dehydrogenase virus (LDV) as the inhibitory component and analysis of the mechanism of inhibition. J Exp Med 143: 100–113 (PMID 1244415) (full text)
- Mphahlele MJ, Lau GK, Carman WF. (1998) HGV: the identification, biology and prevalence of an orphan virus. Liver 18: 143–155 (PMID 9716223)
- Potharaju NR, Potharaju AK (2006) Is Chandipura virus an emerging human pathogen? Arch Dis Child 91: 279–280 (PMID 16492900) (full text)
- Metzler, Alfred E (January 1991). "The malignant catarrhal fever complex". Comparative Immunology, Microbiology and Infectious Diseases 14 (2): 107–124. doi:10.1016/0147-9571(91)90125-W.
- Duesberg P, Rasnick D. (1998) The AIDS dilemma: drug diseases blamed on a passenger virus. Genetica 104: 85–132 (doi:10.1023/A:1003405220186 PMID 10220905)