LAS VEGAS -- State medical officials are recommending 40,000 people be tested for all strains of hepatitis as well as HIV after a medical center exposed former patients to Hepatitis C.

According to the Southern Nevada Health District, about 40,000 patients at the Endoscopy Center of Southern Nevada were exposed to the disease between March 2004 and January 2008. Doctors have found six acute cases of Hepatitis C in patients from the center during that time.

The infections were apparently spread when anesthesiologists would re-use syringes -- not needles -- to administer medications. Five of the infected patients were thought to have contracted the disease in this manner, officials said.

"Based on the information we discovered during our investigation, it appears the injection practices that can lead to the transmission of hepatitis C and other bloodborne infections have been occurring at this clinic for several years," said chief health officer, Dr. Lawrence Sands. "Hepatitis C is a serious medical condition and infected patients may not have outward symptoms of the disease for many years. As a precaution, and in order to take appropriate steps to protect their health, it is important for these patients to get tested and for anyone with the illness to seek medical treatment."

SNHD officials, along with the Centers for Disease Control and Prevention and office workers, have started another investigation into how the contamination happened and from where it stemmed. They recommend that anyone who may have had a procedure completed at the center be tested for HIV and hepatitis strains B and C, as all of the diseases can be transmitted through the same unsafe injection practices identified as the likely source of transmission.

Investigators wanted to calm those worried about the other bloodborne diseases, saying the risk of transmission of hepatitis B and HIV is lower and no associated cases of hepatitis B or HIV have yet been identified in patients treated for hepatitis C.

Representatives from the Endoscopy Center will be sending out notices to affected patients this week. The SNHD has established a hot line for those who think they may have been infected. They ask anyone who was a patient of the center during that time to call 702-759-4636 or visit the SNHD Web site.