R. Kelly knowingly endangered his alleged victims' lives by giving them sexually transmitted diseases.

Amid the trial, R. Kelly's physician spoke up on Thursday about his treatment of the singer's genital herpes. According to the Chicago-based physician, Kris McGrath, who worked for him for 25 years, R. Kelly began receiving the treatment in 2007.

The internist appeared before the Brooklyn federal court under a subpoena after the prosecutors alleged that he knowingly spread his disease to multiple people.

McGrath revealed he served as the singer's doctor since 1994. But years later, he diagnosed him with a sexually contagious disease. He told the court that he began suspecting the singer's genital herpes as early as June 2000.

The disgraced musician reportedly showed symptoms of the disease, prompting him to undergo a test to detect the virus. However, the result came back negative at that time.

Per McGrath, the timing of the test played an important role since the test can give false-negative results at times.

"I did not conclude that he did not have herpes," McGrath said of the medical records the prosecutors obtained.

Doctor Warned R. Kelly About the Disease

In the same court appearance, R. Kelly's physician reportedly asked him to inform his sexual partners about the disease. By doing so, they can decide whether or not to have interaction with him.

McGrath added that it is recommended to treat genital herpes with Valtrex. It is a type of drug that can be prescribed for a short time to manage the symptoms. However, he explained that a patient must take the medication every day if he outbreaks the disease more than three times a year.

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He recalled how the singer or his associates always reached out to refill drugs at a Walgreens pharmacy.

Meanwhile, despite detailing what happened, defense attorney Nicole Blank Becker questioned him for not documenting the genital herpes diagnosis.

The documents, however, revealed that his earliest documentation of the doctor giving him the drug was in March 2007. On the other hand, the first record that showed R. Kelly had a history of genital herpes was written on his medical record in 2011.

During that time, his office already shifted from paper medical records to electronic ones.

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