Not to mention you can also get Hepatitis B and HIV the virus that causes aids.
If you are using please get clean needles.
Is there a needle exchange program where you live?
Since the virus needs blood to blood transmission to spread, yes, needles do so very effectively.
If you are sharing needles with people, get checked.
There is no carrier state in hepatitis C. Anyone who has been exposed to the virus, whether they are cured or not, has the antibody. If a person is cured, they cannot transmit the virus. If they have the virus (found by HCV/RNA in the blood) then they can transmit it. Sharing needles is a very efficient way of transmitting the virus but only if the person has actual virus and not just the antibody.