Image credit: iStock/Peerayot Image credit: iStock/Peerayot

The World Health Organization (WHO) has advised those returning from areas affected by the Zika virus to use condoms for a minimum of six months. WHO is recommending practicing safe sex or abstaining completely, even if they are are trying to conceive, in order to ensure the virus is out of their system.

This new guidance differs from WHO's previous statement on June 7th, which only suggested that men use protection or abstain, with the timeframe given as eight weeks rather than six months.

The updated guidelines, according to WHO, are based on new findings that suggest Zika can be transmitted from asymptomatic males to their female partner and vice-versa. New evidence also suggests that the virus stays in male semen longer than was originally thought.

When infected during pregnancy or at the time of conception, Zika can cause a severe birth defect that results in the baby's head and brain being undersized - microcephaly - and other abnormalities in the brain. This connection was first confirmed late last year in Brazil after more than 1,800 cases of the birth defect were recorded.

Zika has also been found to cause Guillain-Barre, a rare neurological syndrome, in adults along with other disorders.

It was found that the Zika virus could be transmitted to partners when engaging in unprotected sex - primarily through vaginal intercourse - with 11 countries reporting cases by August 26th. The first case of a man catching the virus after engaging in anal sex was reported in February, while suspected transmission through oral sex was documented in April.

So far, the average time that Zika remains in semen after the onset of symptoms is 24 days, however, one man was still infectious after 188 days. WHO has said that its recommendation of six months is conservative but could help avoid the spread of the virus.

WHO has also recommended that pregnant women avoid going to areas that are currently experiencing a spread of the virus, while other people should take precautions against being bitten by mosquitoes to protect against Zika.