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).
They are called obligate intracellular parasites because they must use a host cell's amino acids to synthesize proteins, metabolic enzymes and pathways to obtain energy, ribos â¦ omes to synthesize proteins, and nucleotides for transcription and replication.hey are obligate in the sense that they cannot replicate outside of a host cell. To make a copy of itself, a virus must first enter a cell (intracellular), hijack the machi â¦ nations of said cell (parasitic behavior) and then copy itself. 24 people found this useful.