The Zika virus is expected to spread to parts of Europe in late spring and summer, health leaders have said.
And as this graphic shows, France and Spain - the two most popular foreign countries for UK travellers - have been identified as having a "moderate" risk.
According to the latest travel trends data from the Office for National Statistics, France and Spain host 12 million and eight million annual overnight visits from the UK respectively.
If the virus spreads to France, there could be implications for the impending Euro 2016 championships. Thousands of supporters from across the UK will travel there for the tournament, which begins on June 10.
Many of our other top holiday spots have also been identified as having a "moderate" risk or transmission of the Zika virus - Italy, Croatia, Greece, Turkey and Switzerland.
However, official advice for UK travellers remains unchanged.
And following the announcement that the virus is expected to spread to parts of Europe, Thomas Cook issued a statement which read: "The health and safety of our customers is our top priority.
"We will continue to monitor the World Health Organisation's advice regarding the Zika virus closely and review our policy as required. Should the current situation change, we will actively contact our customers to offer assistance."
The National Travel Health Network and Centre is advising pregnant women to postpone non-essential travel to areas where Zika virus outbreaks are ongoing until after they have given birth.
A spokeswoman for UK travel organisation Abta said the number of UK travellers who have cancelled trips as a result of the virus is "minimal".
She went on: "According to the European Centre for Disease Protection and Control, there has been no active local Zika virus transmission contracted within Europe.
"The new World Health Organisation risk assessment relates to potential, future risks in certain European destinations."