According to the survey, more than half of the Britons polled did not use extra protection to avoid HIV and 22 per cent thought that Aids could be caught by kissing.

Health campaigners said that the growing ignorance was a result of the Government’s failure to promote public awareness and poor sex education.

The Family Planning Association said: “We do not have mandatory sex and relationship education in schools and what does get taught is part of science. But it is not good enough just to talk about biology. Young people need to be taught how to negotiate using a condom.”

The Eurobarometer survey for the European Commission asked 25,000 people across the European Union how much they had changed their sexual behaviour in response to Aids. It comes after a similar survey in 2002. The results suggested that Hungarians had changed their behaviour the most by reducing their sexual partners. A quarter of Britons polled said that they were less likely to be promiscuous, the worst record after the Netherlands.

Britain was below the European average in regard to taking precautions during sex. Some 46 per cent of Britons said that they insisted on extra protection to avoid HIV, putting Britain 15th in the sexual safety league. France, with 52 per cent, was ranked 11th and Italy, with 51 per cent, was ranked 12th against an average of 48 per cent. Cyprus and Austria were at the top of table, with two thirds of respondents insisting on protection, and Lithuania was last on 34 per cent.

The growing ignorance of British respondents to sexual health questions was highlighted by the researchers.

Only 56 per cent of Britons surveyed knew that Aids could not be caught by sharing a beer glass, down 6 percentage points on 2002, and 76 per cent knew that HIV could not be passed on by a meal cooked by someone with the virus, a drop of 7 percentage points.

An EU spokesman said: “We are concerned that young people seem to be forgetting some of the basic messages in public health campaigns.”

According to the European Centre for the Epidemiological Monitoring of Aids, Britain has the fifth-highest level of HIV infection in Europe, with 126 cases per million of population. The Netherlands has the ninth.

INFECTION FEARS

Percentage of people seeking fewer sexual partners because they fear HIV/Aids; and diagnoses per million in 2004

1 Dutch (20 per cent), 72.0

2 British (27), 122.1

3 Irish (27) 89.0

4 French (28) n/a

5 Danish (28) 54.3

6 Latvian (29) 141.3

7 Spanish (31) n/a

8 Portuguese (32) 280.5

9 Swedish (36) 47.9

10 Belgian (36) 95.2

Source: Avert Aids charity

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