An e-mail to the student body Monday said the illness "is relatively rare in the United States and other developed countries."
"Typically, patients make a full recovery after the administration of antibiotics," Vice President for Student Affairs Zauyah Waite wrote. "To avoid becoming sick simply use common practices such as hand washing and avoid sharing food and drink with others."
The woman undergraduate was an international student who arrived from abroad two weeks ago, the Pittsburgh Post-Gazette reported.
She was at a UPMC hospital for treatment, school spokesman Paul Kovach said, and testing of the woman's friends showed they did not have the disease.
Kovach declined to release further information, including whether or not the student lived on campus.
About 400 people contract the illness annually in the United States and about three-quarters of them are infected while abroad, the Centers for Disease Control said.