Slow virus explained

A slow virus is a virus, or a viruslike agent, etiologically associated with a slow virus disease. A slow virus disease is a disease that, after an extended period of latency, follows a slow, progressive course spanning months to years, frequently involves the central nervous system, and in most cases progresses to death. Examples of slow virus diseases include HIV/AIDS, caused by the HIV virus,^[1] subacute sclerosing panencephalitis, the rare result of a measles virus infection,^[2] and Paget's disease of bone (osteitis deformans), which may be associated with paramyxoviruses, especially the measles virus and the human respiratory syncytial virus.^[3]

Characteristics

Every infectious agent is different, but in general, slow viruses:^[4]

• Cause an asymptomatic primary infection

• Have a long incubation period ranging from months to years

• Follow a slow but relentless progressive course leading to death

• Tend to have a genetic predisposition

• Often re-emerge from latency if the host becomes immuno-compromised

Additionally, the immune system seems to plays a limited role, or no role, in protection from many of these slow viruses. This may be due to the slow replication rates some of these agents exhibit,^[5] preexisting immunosuppression (as in the cases of JC virus and BK virus),^[6] or, in the case of prions, the identity of the agent involved.^[7]

Scope

Slow viruses cause a variety of diseases, including cancer.

Examples of viral agents

Virus	Virus family	Disease	Typical latency	Transmitted by
JC virus (Human polyomavirus 2)			Years to Life^§	Unknown; possibly contaminated water
	Polyomavirus	BK nephropathy, bladder cancer^[8]	Years to life^§	Unknown; possibly respiratory spread/urine; possibly contaminated water
			1–10 years	Respiratory droplets^[9]
			10–20 years	Respiratory droplets^[10]
			3–12 weeks	Bite of an infected animal^[11]
Human papillomavirus infection	Papillomaviridae	Cancers of the cervix, oropharynx, vulva, anal, penis, vagina and rectum.	Years	Sexual activity^[12]

^§JC virus & BK virus only cause disease in immunocompromised patients

See also

• Clinical latency
• Virus latency

Notes and References

1. Web site: About HIV/AIDS HIV Basics HIV/AIDS . 2019-02-28. U.S. Centers for Disease Control and Prevention . en-us. 2019-03-05.
2. Web site: PubMed Health . National Center for Biotechnology Information, U.S. National Library of Medicine . Subacute Sclerosing Panencephalitis . https://web.archive.org/web/20140225233200/http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002392/ . 25 February 2014 . 10 February 2012 .
3. Roodman GD, Windle JJ . Paget disease of bone . The Journal of Clinical Investigation . 115 . 2 . 200–208 . February 2005 . 15690073 . 546434 . 10.1172/JCI24281 .
4. Book: Slow Viruses & Prions. . Levinson W, Chin-Hong P, Joyce EA, Nussbaum J, Schwartz B . Medical Microbiology & Immunology: A Guide to Clinical Infectious Diseases . 16th . McGraw Hill . 2020 . https://accessmedicine.mhmedical.com/content.aspx?bookid=2867&sectionid=242761049 .
5. Bocharov G, Ludewig B, Bertoletti A, Klenerman P, Junt T, Krebs P, Luzyanina T, Fraser C, Anderson RM . 6 . Underwhelming the immune response: effect of slow virus growth on CD8+-T-lymphocyte responses . Journal of Virology . 78 . 5 . 2247–2254 . March 2004 . 14963121 . 369240 . 10.1128/jvi.78.5.2247-2254.2004 .
6. Pinto M, Dobson S . BK and JC virus: a review . The Journal of Infection . 68 . Suppl 1 . S2–S8 . January 2014 . 24119828 . 10.1016/j.jinf.2013.09.009 .
7. Bradford BM, Mabbott NA . Prion disease and the innate immune system . Viruses . 4 . 12 . 3389–3419 . December 2012 . 23342365 . 3528271 . 10.3390/v4123389 . free .
8. Web site: Haridy R . 2022-02-25 . The new science linking cancer, schizophrenia and MS to viral infections . 2022-02-28 . New Atlas . en-US.
9. Garg RK . Subacute sclerosing panencephalitis . Postgraduate Medical Journal . 78 . 916 . 63–70 . February 2002 . 11807185 . 1742261 . 10.1136/pmj.78.916.63 .
10. Kuroda Y, Matsui M . [Progressive rubella panencephalitis] . Japanese . Nihon Rinsho. Japanese Journal of Clinical Medicine . 55 . 4 . 922–925 . April 1997 . 9103895 .
11. Hemachudha T, Ugolini G, Wacharapluesadee S, Sungkarat W, Shuangshoti S, Laothamatas J . Human rabies: neuropathogenesis, diagnosis, and management . The Lancet. Neurology . 12 . 5 . 498–513 . May 2013 . 23602163 . 10.1016/S1474-4422(13)70038-3 . 1798889 .
12. Book: Soong TR, Milner Jr DA . Human Papillomavirus Infection . https://books.google.com/books?id=YJ_uCQAAQBAJ&pg=PA40 . Milner Jr DA, Pecora N, Solomon I, Soong TR . Diagnostic Pathology: Infectious Diseases . 2015 . Elsevier Health Sciences . 978-0-323-40037-4 . 40 . https://web.archive.org/web/20170911003204/https://books.google.com/books?id=YJ_uCQAAQBAJ&pg=PA40 . 11 September 2017 . live . vanc . dmy-all.