This article was last updated on August 2, 2016\nCheck back in with the UPMC HealthBeat blog for news and updates on the Zika virus\nWhen it comes to the threat of the Zika virus, men need to be aware of risks as well.\nThe virus is particularly worrisome for pregnant women and their unborn babies \u2014 the condition is passed from mother to child during pregnancy and linked to a host of serious birth defects.\nBut researchers in 2016 discovered men can spread the virus to their sexual partners. In fact, the virus can live in semen longer than blood \u2014 up to two months, by some estimates.\n\u201cWe\u2019ve known about the existence of the Zika virus for 50 or 60 years,\u201d said Richard Beigi, MD, vice president of medical affairs and chief medical officer at Magee-Womens Hospital of UPMC. \u201cAnd it was always thought to be primarily mosquito-borne, with sporadic cases suggesting sexual transmission.\u201d\n\u201cWith this new outbreak since late 2015, there\u2019s increasing data demonstrating it can also be a sexually transmitted infection. That\u2019s a relatively new confirmatory finding.\u201d\nThe mosquito-borne Zika virus was first discovered in 1947 in Uganda. By 2016, a Zika outbreak prompted the World Health Organization to declare a \u201cpublic health emergency of international concern.\u201d\nHow Zika Affects Men\nMen who have contracted the Zika virus can transmit it to their sexual partners, according to the Centers for Disease Control and Prevention (CDC). Women who are pregnant or soon to become pregnant can in turn pass the virus to their unborn children \u2014 and risk the development of several serious birth defects.\nIt\u2019s not currently known if women can pass Zika to their sexual partners. Dr. Beigi said the risk of the virus is primarily for couples who are pregnant or planning to become pregnant.\n\u201cIf a woman is not planning to become pregnant and is on highly effective contraceptive, she has little to worry about,\u201d Dr. Beigi said. \u201cThis is primarily an issue for pregnant women, people\u00a0who want to become pregnant, people at risk for unplanned pregnancy, and their sexual partners.\u201d\nSymptoms of Zika in Men\nMany people infected with Zika won\u2019t know they have the disease: As many as three out of four will not develop any symptoms, Dr. Beigi said.\nThe most common Zika symptoms are:\n\nFever\nRash\nJoint pain\nConjunctivitis (red eyes)\n\nThough Zika\u2019s incubation period isn\u2019t known, you should contact a doctor if you develop any of these symptoms within a few weeks of traveling to an area with Zika.\nYou can learn more about symptoms, treatment, and detection by visiting our guide to the Zika virus.\n\u201cIt\u2019s really the minority of people who develop symptoms,\u201d Dr. Beigi said. \u201cBut if you develop those symptoms you absolutely should get checked.\u201d\nZika Guidelines for Men\nIn known cases, men who have transmitted Zika have had either vaginal, anal, or oral sex without a condom, according to the CDC. The organization recommends safe sex or sexual abstinence for those who may have been exposed to the virus:\n\nMen who have been diagnosed with Zika and\/or show symptoms should abstain from sex or use condoms for at least six months after symptoms develop.\nIf a man has traveled to an area with Zika and does not develop symptoms, couples should consider using condoms or avoiding sex for at least 8 weeks.\nIf a couple is living in an area with Zika they should consider using condoms or avoiding sex while Zika is still in the area.