WASHINGTON: The World Health Organisation issued a global warning on Friday, urging pregnant women to avoid travelling to active Zika zones as the link between this virus and birth defects grew stronger.

The US Centre for Disease Control and Prevention has also issued a similar warning.

“Based on the latest evidence that Zika virus infection during pregnancy may be linked to microcephaly in newborns, WHO is issuing further precautionary travel advice to women who are pregnant and their sexual partners,” said a statement WHO sent to media outlets across the globe.

“Women who are pregnant should discuss their travel plans with their health care provider and consider delaying travel to any area where Zika infection is occurring,” it added.

The world body has already declared Zika and the link to birth defects an international emergency and is coordinating efforts to develop vaccine and better tests for Zika. Zika is also suspected of causing a rare but dangerous paralysing condition called Guillan Barre syndrome.

At a news conference in Geneva, a WHO official said that possible Zika vaccines could still be months away from broad trials.

Dr. Marie-Paule Kieny, WHO assistant director-general for health systems and innovation, said that “vaccines are at least 18 months away from large-scale trials”.

Dr. Kieny pointed out that two vaccine “candidates seem to be more advanced: a DNA vaccine from the US National Institutes for Health and an inactivated product from Bharat Biotech in India”.

So far, there’s no vaccine to prevent Zika infection, mostly because the virus had been considered harmless.

Zika is closely related to dengue and yellow fever. Health experts warn that the mosquitoes that carry this virus thrive in warmer climates, such as that of India and Pakistan.

Published in Dawn, February 13th, 2016