The Zika virus could spread across Europe, particularly to hotter countries, the World Health Organisation has warned.
WHO chiefs say the risk of the virus spreading would increase in spring and summer as temperatures rise.
Currently Zika, which has been declared an international health emergency, is only known to spread through the bites of the Aedes aegypti mosquito.
But some experts believe it could potentially be carried by the tiger mosquito, which is rife in Spain and other parts of the Mediterranean.
Spanish officials confirmed on Thursday that a pregnant woman is among seven people identified as being infected with the Zika virus in Spain after visiting affected countries.
The woman, who had travelled to Colombia and is in her second trimester, is under medical supervision in the northeastern region of Catalonia.
Earlier this week, Prof Frederic Bartumeus, a research professor based in Catalonia, told the Telgeraph he can imagine ‘hundreds of thousands of Zika cases in Spain’ if the tiger mosquito species begins to spread the disease.
Italy and the south of France could also be affected.
Although the Zika virus has mild symptoms, it has been strongly linked to birth defects such as abnormally small heads.
Women are being warned to avoid Zika-hit countries if they are pregnant or are thinking about becoming pregnant.
Britain’s NHS has now banned travellers who have been to Zika-hit countries from giving blood for 28 days after their return.
After nine cases in Florida, State Governor Rick Scott has declared a health emergency in the four counties affected – Miami-Dade, Lee, Hillsborough, and Santa Rosa counties.
All of the cases occurred in people who have travelled to Latin America and the Caribbean, where the virus has been spreading.
