The hepatitis C virus infects the liver and circulates in the bloodstream. It is primarily transmitted through blood-to-blood contact. Infections most frequently occur when the blood of a person infected with hepatitis C directly enters the bloodstream of someone else. The most common way to catch hepatitis C is by sharing needles or other injection drug equipment. Other possible ways to contract hepatitis C include exposure to infected blood during tattooing or body piercings, accidental exposure in the workplace or during a medical procedure, sharing personal care items and through blood transfusions. Mothers with hepatitis C can also pass the virus to their babies. In certain situations, hepatitis C can be transmitted through sexual contact.
Street Drug Use
Most people catch hepatitis C by sharing needles, syringes or other street drug paraphernalia -- even if you've done so only once. According to the Centers for Diseases Control and Prevention, approximately one-third of people aged 18 to 30 who inject drugs have contracted the hepatitis C virus, or HCV. More than 70 percent of people 50 and older who currently or formerly injected street drugs have been infected with HCV. It might also be possible to contract hepatitis C by sharing drug equipment used to inhale or snort drugs, such as cocaine or methamphetamine. All it takes is a small droplet of blood from an infected person on shared drug equipment to catch hepatitis C.
Approximately 6 out of 100 babies born to mothers with hepatitis C become infected at the time of birth, according to CDC. The risk of passing hepatitis C from mother to baby increases if the mother also has human immunodeficiency virus, or HIV. A June 2014 "Clinical Infectious Diseases" article reported that HCV-infected mothers who also have HIV are roughly twice as likely to pass hepatitis to their babies than mothers who have only hepatitis C. The risk of transmitting hepatitis C also relates to the amount of virus present in the mother's blood. The greater the amount of HCV in the mother's blood, the higher the risk is of passing the virus to her baby.
Tattoos and Body Piercings
You can catch hepatitis C from getting a tattoo or body piercing with equipment that has not been properly sterilized. Blood from an infected person may still be on the equipment or in the tattoo ink. The tiny breaks in the skin that are made during tattooing or body piercing create routes of entry into the bloodstream if HCV-contaminated equipment is used. A November 2010 article published in the "International Journal of Infectious Diseases" analyzed 83 studies and found an increased risk for hepatitis C associated with having a tattoo done in a nonprofessional setting. However, the risk of catching hepatitis C from a professional studio with sterile equipment appears low.
If you work in a field where you might be exposed to another person's blood or body fluids -- such as medicine, dentistry, policing, firefighting or even coaching -- you can potentially contract hepatitis C due to accidental exposure on the job. The risk is greatest with accidental sticks from a used needle. CDC estimates that approximately 1.8 percent of people exposed to HCV-positive blood through an accidental needle stick become infected. Infection is less likely to occur from splashes of HCV-infected blood or body fluids into the eye, or open cuts or sores on your skin.
Blood Transfusions and Blood Products
In the past, there was a significant risk of catching hepatitis C through blood transfusions or from receiving other blood products, such clotting factors to treat bleeding disorders or immune globulin to help fight bacterial infections. However, this route of infection is now rare. Since 1992, all blood and blood products have been screened to ensure they do not contain the hepatitis C virus. According to CDC, the risk of hepatitis C infection through blood transfusions is less than 1 chance per 2 million units of blood transfused.
Contaminated Medical Equipment
Medical equipment that has not been properly cleaned or sterilized can be a source of hepatitis C infection if it is contaminated with blood or body fluids from an infected person. Hepatitis C infections from contaminated medical equipment are uncommon. CDC reports that 239 people in the United States were infected this way from 2008 through 2014 due to lapses in safety and sanitation measures. When these measures are followed, however, there is virtually no risk of hepatitis C infection from a medical procedure.
Shared Personal Care Equipment
Sharing personal care equipment that may be contaminated with blood -- such as clippers, nail scissors, razors and toothbrushes -- might lead to hepatitis C infection. This can occur at home if you live with someone who has hepatitis C or at places such as nail salons, if the equipment is not properly sterilized. Hepatitis C can only be caught this way if blood from an infected person remains on the personal care equipment and gains entry into your bloodstream through a small nick, scrape or cut.
It is rare to catch hepatitis C through sexual contact, though it is possible in some situations. This is because the virus is present in body fluids of someone with the illness, such as semen and vaginal secretions. The risk of hepatitis C transmission in heterosexual couples in long-term, exclusive relationships is extremely low, according to a research study published in March 2013 in the journal "Hepatology." There is a higher risk, however, in men who have sex with men -- especially if they also have HIV. Having a sexually transmitted infection and engaging in sex practices that cause bleeding also increase the risk of hepatitis C.
Warnings and Precautions
You can reduce your risk of catching hepatitis C through the following methods:
-- Do not share needles or other street drug paraphernalia.
-- Ensure you only patronize nail salons or body art parlors that sterilize equipment properly between clients. Many people take their own manicure/pedicure kit to salons.
-- Do not share personal care equipment such as razors, nail grooming equipment and toothbrushes.
-- Follow safety measures at work to reduce the chance of a workplace accident. If you are exposed to blood or body fluids at work, contact your supervisor and doctor immediately.
If you think you might have hepatitis C or have possibly been exposed to HCV, see your doctor or check with your local health department about getting tested.
Medical advisor: Tina St. John, M.D.