What are Neurotropic viruses?
Neurotropic viruses definition
A neurotropic virus is said to be neuroinvasive if it is capable of accessing or entering the nervous system. It is neurovirulent if it is capable of causing disease within the nervous system. Both terms are often applied to central nervous system infections. Some neurotropic viruses are highly neuroinvasive for the peripheral nervous system (e.g. herpes simplex virus). Important neuroinvasive viruses include polio virus, which is highly neurovirulent but weakly neuroinvasive. The rabies virus, which is highly neurovirulent but requires tissue trauma (often resulting from an animal bite) to become neuroinvasive.
Neurotropic viruses Examples
Neurotropic viruses causing acute infection include Japanese equine encephalitis, Venezuelan equine encephalitis, and California encephalitis viruses, polio, coxsackie, echo, mumps, measles, influenza, and rabies viruses as well as members of the family Herpesviridae such as herpes simplex, varicella-zoster, cytomegalo and Epstein-Barr viruses.
These causing latent infection include herpes simplex and varicella-zoster viruses. These causing slow virus infection include measles, rubella and JC (the JC virus or John Cunningham virus, is a type of human polyomavirus (formerly known as papovavirus)), viruses, and retroviruses such as human T-lymphotropic virus 1 and human immunodeficiency virus. Prion, which is not a virus but a host-derived non-physiological protein, causes transmissible spongiform encephalopathy such as Kuru and Creutzfeldt-Jakob disease that resemble slow virus infection.
All seven of the known human coronaviruses are neurotropic, the common cold viruses mainly in vulnerable populations while the more virulent SARS-CoV-1, MERS, and SARS-CoV-2 frequently attack the nervous systems (primarily in mammal animal models).
Japanese encephalitis virus is a mosquito-borne flavivirus that can cause encephalitis and death in horses and humans. It is an emerging disease of international concern because it has been spreading into previously nonendemic areas. Major epidemics may occur where the virus moves into new areas, but many infections maybe subclinical.
Examples of the MERS Virus