A prank caller posing as a Searle Student Health Service employee has called three Northwestern women since April to falsely give them positive lab results for sexually transmitted diseases, officials said.

Independent of the incidents, university health officials said they hope to launch a new lab-result disclosure system within two months to improve confidentiality and reassure students that such calls are false.

In each of the prank calls, a female voice told the three women — two current students and one recent graduate — on answering machines that they had tested positive for an STD. One woman was told she had AIDS.

However, none of the three women had been tested for STDs at Searle, and it is against protocol for such results to be disclosed on an answering machine, said Dr. Donald Misch, NU’s director of health service.

“We are not going to call and leave you a message and say, ‘Hi, you have AIDS,'” Misch said. “If you hear that, it wasn’t us.”

The most recent incident took place in December.

Weinberg junior Hannah Yoo said that when she returned home from a weekend trip during Spring Quarter, her roommate informed her she had an important message on the answering machine.

Yoo said a woman — who identified herself as “Melanie,” a Searle employee — told Yoo she had access to her medical records and that Yoo had tested positive for unspecified STDs. The woman advised Yoo to return the phone call to discuss the results and set up a counseling appointment.

Yoo said she was stunned Searle would leave such sensitive information on an answering machine. But she was also suspicious.

“It just seemed really rehearsed,” Yoo said, adding that she had never been tested for STDs.

Yoo said she thought Searle had confused her with another student. She called Searle the next morning and was told the phone call must have been false.

Misch said he believes the prankster is likely a student.

“We have absolutely no indication that anyone in the health services is doing it,” Misch said.

As investigations continue Searle officials are planning to begin using a pilot phone system that will allow students to receive lab results from an automated answering system.

The system is not in response to the prank phone calls — Misch, who took over as Searle’s leader in July, said he has been planning to install it since last year. The new system is expected to help prevent such pranks from being taken seriously.

It is unclear what punishment the prankster will receive if she is caught.

Yoo said she notified University Police about the phone call and that a police officer came to her dorm room to listen to the message on her answering machine.

She said police told her that because the message did not constitute a threat, the police could take no action.

According to UP Assistant Chief Daniel McAleer, such a call would constitute harassment, but police cannot trace a call that has already been made.

Misch speculated the offender would be punished by the University Hearing and Appeals System if she is a student.

The Daily’s Scott Gordon contributed to this story.