There are more details than merely having injected drugs. Blood transfusions have spread Hep C in hospital settings before widespread knowledge of the disease.

There are more details than merely having injected drugs. Blood transfusions have spread Hep C in hospital settings before widespread knowledge of the disease. Infected mothers can pass it to children through childbirth. The disease wasn't even identified until, what, late 1980s? Meaning that there are people who contracted it before then who may not know.