Polio, or poliomyelitis, is a highly contagious viral infection that can lead to paralysis, breathing problems, or even death. The term poliomyelitis is from the Greek polios poliÃ³s meaning, grey myelos myelÃ³s referencing the, spinal-cord and itis. Meaning inflammation polio can be classified as either symptomatic. or asymptomatic
1 Prions are proteins that can force conformational changes in natural proteins and seem to cause disease (kuru, new variant Creutzfeldt-Jakob disease, and fatal familial insomnia).  A virus is an obligate intracellular pathogen (meaning that it must live within the cells of its host in order to reproduce).
Virus Replication. Viruses are intracellular obligate parasites which means that they cannot replicate or express their genes without the help of a living cell.A single virus particle (virion) is in and of itself essentially inert. It lacks needed components that cells have to reproduce.irus Replication. Viruses are intracellular obligate parasites which means that they cannot replicate or express their genes without the help of a living cell.