Most at risk are tourist island of Madeira and Georgia and the Black Sea coast.
That is, the regions where the mosquito - Aedes aegypti - which spreads the virus there.
WHO is worried, however, that many more countries may suffer as a completely different myggart - Aedes albopictus - has also been identified as a potential virus carriers.
In the United States as far north as New York and there is nothing to say that it would not be able to come to Sweden, says Anders Lindström, entomologist and insect expert at the Swedish Veterinary Institute SVA
The risk of zikaviruset will gain a foothold in Sweden because of this mosquito, he assesses to be small.
- Although Aedes albopictus come here it will be probably no large populations, since it requires fairly high temperatures for a long time to be able to multiply in large quantities, says Anders Lindström.
Right now, South and Central America hard hit by zikaviruset.