A Brazilian soldier shows a pamphlet that will be distributed in Rio de Janeiro. The pamphlet reads, "A mosquito is not stronger then an entire country." (Ricardo Moraes/Reuters)

The World Health Organization on Friday issued its first set of recommendations for travel to Zika-impacted countries. Its advice to pregnant women — to consider delaying their trips — is similar to language used by U.S. officials and represents a recognition of the mounting evidence of a link between the mosquito-borne virus and birth defects in newborns.

The WHO guidance also included strong language regarding the possible risk of sexual transmission, advising all travelers but especially pregnant women and their partners returning from an area where Zika is circulating to use condoms.

The group said that there's no reason to recommend any travel or trade restrictions at this time. "Countries reporting sporadic Zika infections in travellers arriving from affected countries pose little, if any, risk of onward transmission," the WHO said in a statement.

Speaking at a panel at the American Association for the Advancement of Science on Friday, the WHO's Chris Dye said that the evidence regarding a link between microcephaly — a congenital issue in which babies are born with shrunken heads — and Zika is mounting and that at this point they are proceeding as if "Zika is guilty until proven innocent."

Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases, said that pregnant women should "seriously consider postpoining your travel until this situation gets sorted out."

The WHO guidelines caution travelers to stay alert about the latest news about Zika and to take steps to protect themselves against mosquito bites during their trip. The WHO is advising travelers to:

  • use insect repellent: repellents may be applied to exposed skin or to clothing, and should contain DEET. Repellents must be used in strict accordance with the label instructions;
  • wear clothes (preferably light-colored) that cover as much of the body as possible;
  • use physical barriers, such as screens, closed doors and windows;
  • sleep under mosquito nets, especially during the day, when Aedes mosquitoes are most active;
  • and identify and eliminate potential mosquito breeding sites by emptying, cleaning or covering containers that can hold even small amounts of water, such as buckets, vases and flower pots.

Read more:

Miscarriages reported in 2 U.S. women with Zika virus, CDC says

NIH officials accelerate timeline for human trials of Zika vaccine, saying they will now begin in the summer

Why Zika is a ticking 'time bomb' for Latin America

Beyond Zika: The map of things that keep NIH’s infectious diseases director up at night

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