Nearly 100 patients of Ballad Health in Johnson City, Tennessee, were possibly exposed hepatitis B and C and HIV during a May 3 visit, reports WJHL.com. They received phone calls and letters from the Johnson City Medical Center warning them of the incident and encouraging them to get tested as a precaution.

The letters—you can read one of them here—described the risk as “extremely low” and stated that the potential exposure stemmed from the actions of a single nurse who violated the health center’s medical policy and “improperly handled controlled substances.” The letter also clarified that Ballad Health would arrange and pay for the hepatitis and HIV tests.

Although WJLH.com did not specify the type of violation, HIV and hepatitis B and C can be transmitted via blood-to-blood contact, including through unsterile or shared needles and medical equipment that comes in contact with blood. Cases of health care workers injecting themselves with drugs prescribed to patients—notably opioid painkillers—and reusing the syringes have also been reported. For an example from last year, see “5 Years in Prison for Utah Nurse Who Passed on Hep C to Patients.”

In addition, failure to follow precise sterilization procedures has resulted in numerous health care centers, dentists and beauticians sending out similar warnings to clients. (For the most recent example in HepMag.com, see “Dental Clients Test Positive for Hepatitis C but Lose a Malpractice Lawsuit.”)

Ballad Health issued a separate statement explaining that the potential exposure came to light after a longtime nurse witnessed “something unusual and reported it immediately to superiors.” The person responsible was associated with a nursing contract agency and is no longer allowed to work at Ballard, reports WJHL.com. “Johnson City Medical Center is proud of the nurse who saw something and said something,” the statement reads. “We are grateful for the example this nurse set. She is a hero, and we celebrate her professional act.”

Amy Hunter, one of the patients who received the letter, told WJHL.com in a different article and news segment, which you can watch above, that she has been on “an emotional roller coaster” while waiting for her test results. She’s also looking into her legal options and wants to know what steps Ballard Health is taking to ensure this doesn’t happen to anyone else.

Hepatitis refers to inflammation of the liver. When untreated, it can lead to scarring of the liver (cirrhosis), liver cancer, the need for a liver transplant and death. Hepatitis can be caused by several factors, including toxins, too much alcohol, autoimmune diseases, fat in the liver and viruses, including the three most common ones: hepatitis A, B and C. According to “Hepatitis C Transmission and Risk,” part of Hep’s Basics of Hepatitis, hep C is most easily spread through:

  • Sharing needles and other equipment (paraphernalia) used to inject drugs

  • Blood transfusions and organ transplants before July 1992

  • Sexual contact with someone who has hep C

  • Having a mother who had hep C when you were born.

HIV, in contrast, is a virus that attacks the immune system. Over several years, the immune system becomes depleted, and the body isn’t able to fight infections, leading to an AIDS diagnosis. Although there is no cure for HIV, many safe and effective treatments—often just one pill a day—are available. The medications help people living with HIV enjoy long and healthy lives and keep them from transmitting the virus to others. For more, see the Basics of HIV/AIDS in POZ.com, a sister publication of HepMag.com.