Can viruses form symbiotic relationships with humans?

Yes These guys are often thought of nothing but evil. In fact, in the Matrix Agent Smith says that humans are like a virus, since neither benefit their host. This metaphor is brought up in the Kingsmen as well. read more

External viruses can also lead to beneficial relationships. Hepatitis G, a nonpathogentic virus, is believed to actually suppress HIV progression in humans. So yes, viruses do form mutually beneficial relationships with animals, even humans. read more

I think the word you are going for is commensalism. Symbiosis is a general term for multi-organism relationships that can encompass parasitism, mutualism, or commensalism. Commensalism a symbiotic relationship in which both parties benefit from the interaction. read more

Fungi are poor organisms for symbiotic relationships with human as compared to viruses. The relationship between fungi and its host is most likely to be mutalistic in most cases. Lastly, for symbiosis to occur in protists, primary and intermediate hosts are required. (Kimball) Although protists, fungi, and bacteria can all form symbiotic relationships within a host, viruses stand about the other groups in forming symbiotic relationships. read more