Hi Jessica, an easy way is to run a blood test, then you'll know everything you want to know. The following is what I can share. If it's hepatitis A - hepatitis A is a self-limited disease that does not result in chronic infection. It's been 49 years since you used that contaminated blood, you should have recovered long time ago. If it;s hepatits B - when the virus enters the body, the body starts to fight, in some cases, the body can fight it off within months, in some other cases, the body failed to fight it off, when it lasts for 6 months, you're a carrier. You can't donate blood, plasma, body organs, etc. If it's hepatits C - many people who are infected with the hepatitis C virus do not know they are infected because they do not look or feel sick. Of course you can't donate blood either. If it's hepatitis D - hepatitis D is uncommon in the United States. Hepatitis D only occurs in people who are infected with the hepatitis B virus because HDV is an incomplete virus that requires the helper function of HB