Since there is a potential for blood-to-blood contact to occur during a manicure or pedicure, theoretically, there is a risk. So far, there has only been one documented case of hepatitis C transmission occurring as a result of getting one’s nails done. With millions of people using nail salons, this indicates a low risk.
Although the risk may be more theoretical than actual, you can take steps to protect yourself. Inspect manicure tools, asking about what disinfection process is used. Tools that are disposable offer a higher degree of protection. A good option is to bring your own equipment, especially cuticle scissors. If you have any doubts about safety, speak up.