TEL AVIV – Women visiting countries afflicted with the Zika virus should refrain from getting pregnant while there and for four weeks after leaving the country, the Israeli Health Ministry advised Tuesday.

The recommendation also stated that people visiting Zika areas should refrain from donating blood for 28 days after their return, Haaretz reported.

The Health Ministry assesses that a month is long enough for people to be certain that they haven’t contracted the virus, whose incubation period is usually three to 12 days.

The virus is suspected of causing microcephaly, a severe condition in which babies are born with underdeveloped brains, though the connection has yet to be clinically proven.

Previously it was believed that Zika could only be contracted by a bite from an infected mosquito, though the ministry’s new directives seem to indicate that Zika can be contracted through sexual intercourse.

“In a few cases, men who contracted the virus infected their partners through intercourse,” the ministry’s statement said. It therefore advised people who visit a country suffering from Zika “to use a condom while having sexual relations during their stay there, and also for four weeks after leaving the danger zone.”

The ministry had previously recommended that pregnant women or women planning to get pregnant postpone trips to affected areas. The recommendations also advised anyone traveling to affected countries to take precautions against mosquito bites.

The ministry’s statement included a list of countries defined as risk zones, broken down by region as follows: In the Americas: Brazil, Venezuela, Panama, Honduras, Colombia, El Salvador, Surinam, Guatemala, Paraguay, Mexico, Martinique, French Guiana, Puerto Rico, and Haiti. In southeastern Asia: Indonesia, Cambodia, Malaysia, and Thailand. In the Pacific Ocean: Samoa, Fiji, Vanuatu, New Caledonia, the Solomon Islands, the Cook Islands, eastern Micronesia, and French Polynesia. In Africa: Cape Verde, Angola, Burkina Faso, Cameroon, Central African Republic, Ivory Coast, Nigeria, Senegal, and Uganda.

The World Health Organization declared Zika a global health emergency on Monday. It noted that the virus was found in the brains of five out of 49 babies who died of microcephaly recently. The WHO also said it will take more than a year to develop a vaccine against the virus.