The survey says sex workers are highly mobile in Europe
Romania has overtaken Russia as the top country of origin of migrant sex workers in the EU, a survey of prostitution across the EU has found.
In 2006 the top countries of origin were Russia, Ukraine and Romania - in that order, the Tampep network reports.
But in 2008 the top three were Romania, Russia and Bulgaria. Romania and Bulgaria joined the EU in 2007.
EU-funded Tampep collects data from welfare groups and public health bodies that monitor and help prostitutes.
Tampep's data collection is part of an effort to curb the spread of HIV/Aids and other sexually-transmitted diseases.
According to the survey, Central and Eastern Europe, including the Baltic and Balkan countries, account for around 70% of migrant sex workers in the 27-nation EU.
The next largest groups come from Africa (12%) and Latin America and the Caribbean (11%).
Tampep, which is based in Amsterdam, reports that about 70% of all sex workers in the older EU member states are migrants. The proportion of migrants is far smaller in the new member states which joined the EU in 2004 and 2007.
Italy, Spain, Austria and Luxembourg report that migrants comprise 80% to 90% of the sex worker population.
The greatest balance between migrants and nationals is found in Portugal (56% migrants) and the UK (41% migrants). In the UK, the highest concentration of migrant sex workers is in London - 80%.
"Since the accession of Bulgaria and Romania to the EU, many migrant sex workers from these countries are less restricted due to their new legal situation," the report says.
"In addition, street work enables them to work occasionally and change their location when they choose, creating a higher degree of mobility."