First sexually transmitted Zika case reported in Pa.

A Pennsylvania resident traveling outside the state contracted the Zika virus and transmitted it to his or her partner after returning to the commonwealth, the state Department of Health announced Thursday. It marks the first known instance of the virus being sexually transmitted in the state.

Health Secretary Karen Murphy released no details about the gender of the residents, their hometowns, or where the infection was acquired.

Pennsylvania has reported 95 cases of Zika, according to the Department of Health's website. Until Wednesday, none of the victims had contracted the illness here in the state.

"In light [of this case], we remind residents to practice safe sex, especially if they have traveled to an area with Zika-infected mosquitoes," Murphy said in a statement. "Infections with the Zika virus may be present without symptoms.  If you have traveled to an area where Zika virus is present, condoms or other barrier protection methods should be used during sex for eight weeks upon return to prevent sexual transmission."

Zika is a mosquito-borne virus that can cause fever, rash, joint pain, and pinkeye. Though the symptoms are rarely grave, infection during pregnancy has been linked to serious birth defects.