Per the US CDC Hepatitis C FAQ for the public
“Can you get Hepatitis C by getting a tattoo or piercing?
A few major research studies have not shown Hepatitis C to be spread through licensed, commercial tattooing facilities. However, transmission of Hepatitis C (and other infectious diseases) is possible when poor infection-control practices are used during tattooing or piercing. Body art is becoming increasingly popular in the United States, and unregulated tattooing and piercing are known to occur in prisons and other informal or unregulated settings. Further research is needed to determine if these types of settings and exposures are responsible for Hepatitis C virus transmission.”
So assuming she went to a licensed piercing shop they would be following standard precautions and there should be no risk.
Again from the CDC
“Who is at risk for Hepatitis C?
Some people are at increased risk for Hepatitis C, including:
Current injection drug users (currently the most common way Hepatitis C virus is spread in the United States)
Past injection drug users, including those who injected only one time or many years ago
Recipients of donated blood, blood products, and organs (once a common means of transmission but now rare in the United States since blood screening became available in 1992)
People who received a blood product for clotting problems made before 1987
Hemodialysis patients or persons who spent many years on dialysis for kidney failure
People who received body piercing or tattoos done with non-sterile instruments
People with known exposures to the Hepatitis C virus, such as
Health care workers injured by needlesticks
Recipients of blood or organs from a donor who tested positive for the Hepatitis C virus
Children born to mothers infected with the Hepatitis C virus
Less common risks include:
Having sexual contact with a person who is infected with the Hepatitis C virus
Sharing personal care items, such as razors or toothbrushes, that may have come in contact with the blood of an infected person”
Any licensed barber or beauty parlor should also be using universal precautions to prevent spread of infection. The hair cut specialists receive training in proper procedures.
I would not be concerned if you are going to a licensed store. Having a professional haircut is not on the CDC’s list as a risk factor.
Found this on a UK hepatitis C web site
“Potentially, Hepatitis C could be spread through equipment used by hairdressers and barbers. Scissors, razors and clippers can cut, nick or graze the skin, enough to draw blood. ... It's important to stress that the risk of contracting Hepatitis C from a hair cut is absolutely minimal.“