Geneva - People who travel to Zika-hit areas should practice safe sex or have no sex at all for at least eight weeks after their return to avoid sexual transmission of the virus, the World Health Organisation said on Tuesday.
That is double the one month of safe sexual practices previously recommended by WHO, which explained that new studies showed the Zika virus could survive in sperm longer than previously thought.
The recommendation is only for men and women who present no symptoms of the virus, which experts agree is behind a surge in cases in Latin America of microcephaly - a serious birth defect in which babies are born with unusually small heads and brains.
If the male partner has shown symptoms of Zika, the couple should practice safe sex or abstain for six months, "to ensure that the infection has left the body and the virus will not be passed to... the partner," WHO spokesperson Christian Lindmeier told reporters.
Women who are pregnant or trying to become pregnant should avoid travelling to areas affected by Zika all together and if their male partner has travelled to such an area, the couple should practice safe sex or abstain for the remainder of the pregnancy, it said.
Sexual transmission
It remains unclear how long the virus can persist in body fluids, but a report issued recently showed the sperm of a man returning to Britain from Cook Island remained positive for the virus 62 days after he first detected symptoms, WHO said.
Zika is mainly spread by two species of Aedes mosquito, but has also been shown to transmit through sexual contact.
The virus, which also causes the rare but potentially fatal neurological disorder Guillain-Barre Syndrome, is mainly spread by two species of Aedes mosquito.
But WHO warned on Tuesday that "mounting evidence has shown that sexual transmission of Zika virus is possible and more common than previously assumed."
For people living in areas where Zika is spreading, controlling the spread is obviously more complicated.