The hepatitis C virus is transmitted via blood, primarily by sharing needles when using drugs. Snorting drugs can also transmit hepatitis C. With a shared tube or rolled-up note, the virus can be transferred from the lightly bleeding nasal passage of one person to another.
There is also a very high risk of infection from unprofessional tattooing or piercing with unclean needles.
Hepatitis C is only rarely transmitted during sex. However, people with HIV appear to be at an elevated risk. In recent years, the number of HIV-positive people who are infected with hepatitis C has risen dramatically. Transmission is mainly possible during unprotected anal sex or so-called "fisting" (inserting most of, or all, of the hand into the rectum.