More than 4,000 could have been exposed to hepatitis and HIV in a Long Island hospital due to potential blood contamination from insulin pens, ABC reports. South Nassau Communities Hospital, located on 1 Healthy Way in Oceanside, sent letters to 4,247 people informing them about the unsanitary situation, but says that so far only 200 people have signed up for the free and confidential blood testing. Although the testing is voluntary, it is recommended. A dedicated toll-free telephone number has also been set up for patients to schedule a test within 60 days of receiving the letter: 516-208-0029.

Eyewitness News Dr. Sapna Parikh explained the nature of the possible contamination, saying "Insulin pens are injector devices with a built-in insulin reservoir designed to be used multiple times, but for one person…Insulin pens should never be used in more than one person because with each injection, there's a small risk a small amount of blood can go backwards into the cartridge, creating a risk the next time.”

Insulin pens are now banned at South Nassau, and only single-use vials will be used to administer insulin.

The full hospital statement, according to ABC, reads: "Working closely with the New York State Department of Health, South Nassau is voluntarily notifying a specific group of patients that may have received insulin from an insulin pen reservoir (not the pen's single-use disposable needle) that may have been used with more than one patient. The risk of infection from this is extremely low, nonetheless, out of an abundance of caution, the hospital is recommending that patients receiving the notification be tested for hepatitis B, hepatitis C and HIV. While the testing is voluntary, it is recommended. To facilitate the process, the hospital is offering the patients free and confidential blood testing services. It has established a dedicated toll-free telephone number that the patients may call to schedule a blood test within 60 days after receiving the letter. South Nassau has already implemented a hospital-wide policy that bans the use of insulin pens and permits only the use of single-patient-use vials to administer prescribed insulin treatments to patients."