ABSTRACT
The viruses that penetrate the central nervous system (CNS) possess neuroinvasive properties and are usually also neurotropic, meaning that they infect neural cells (neurons and glial cells) and by doing so may also become neurovirulent as they can participate in the development of neurological diseases. In the long list of viruses that are neuroinvasive, neurotropic, and potentially neurovirulent, the coronaviruses, from the order Nidovirales, are prevalent and have been occasionally associated with neuro-degenerative diseases of the CNS including multiple sclerosis, Parkinson’s disease, and even Alzheimer’s disease. Coronaviruses are classified in three different genera, namely a-, fi-, and 7-coronaviruses and are ubiquitous mainly respiratory and enteric pathogens, with neurotropic and neuroinvasive properties in various hosts including humans, cats, pigs, and rodents. Human coronaviruses are recognized respiratory pathogens, however, infectious particles, antigens or RNA, were detected in tissues other than the respiratory tract, including the CNS.
