WHO Strengthens Guidelines to Prevent Sexual Transmission of Zika Virus

— -- The World Health Organization has strengthened its guidelines for Zika due to fears that the virus may persist in bodily fluids for longer than previously thought.

The WHO advised couples to use barrier contraception or abstain from sexual contact for at least eight weeks after returning from an area with ongoing Zika virus transmission. This is double its previous guideline of four weeks.

For men who have symptoms of the Zika virus, the WHO advises them to abstain from sex or use barrier contraception for six months over concerns that the virus could persist in semen. For women who have symptoms of the Zika virus, that recommended period is eight weeks.

Additionally, couples who want to conceive are advised to wait six months if they had any symptoms of the Zika virus. Symptoms can include fever, pink eyes or rash.

The WHO guidelines are now in line with the recommendations from the U.S. Centers for Disease Control and Prevention, which had already advised these same time tables to stop sexual transmission of the virus. The WHO said it is still investigating sexual transmission of the virus and it's not clear if people other than symptomatic men can transmit the virus during sexual contact.

"To date, all published cases of sexual transmission have been from symptomatic male, whose sexual activities may have occurred before, during or after Zika symptom onset, to their partner," the WHO said in its updated guidelines. "It remains unknown if women or asymptomatic men can transmit the virus through sexual activity."

The common symptoms of Zika infection include fever, rash, joint pain and conjunctivitis, according to the CDC. Approximately one in 5 people infected with the virus shows symptoms. Severe complications from Zika infection that require hospitalization are rare, and most people are over the worst of the symptoms after a week, according to the CDC.

The virus has been shown to cause of a rare birth defect called microcephaly, characterized by an abnormally small head and brain, leading to significant developmental issues.