Hepatitis C (green) and polio (red) virus particles, illustration. Both consist of a core of genetic material (RNA, ribonucleic acid) and a protein shell (capsid). The hepatitis C virus particles have a lipid envelope with embedded glycoproteins. The hepatitis C virus is 80 to 120 nanometres in diameter. Poliovirus is 30 nanometres in diameter. Hepatitis viruses cause a liver inflammation called hepatitis. Hepatitis C (HCV) is spread through blood or sexual contact. It can be treated by drugs if diagnosed early, but can cause fatal liver damage including inflammation and scarring of the liver (cirrhosis). Poliovirus infects children and causes the disease poliomyelitis or infantile paralysis. Although it normally causes a mild illness, in some cases it causes damage to the nervous system, which can lead to paralysis or death.