Hector and orphanedhawk's observations are spot on as is your doctor's comment on boiling. However, a properly used pressure vessel kills Hepatitis Virus not by 'boiling' but by the raising of the pressure and the subsequent sudden drop when the pressure is released. This applies to HBV, not sure about HCV.
Bottom line, tattoo artists, dentists, acupuncturists, doctors, nurses, and phlebotomists should all be using one-use, disposable equipment in this day and age.