A public health expert has warned that a crackdown on women who sell sex ahead of next year's Commonwealth Games could make them more vulnerable to violence and health problems such as HIV.

Georgina Perry is service manager for Open Doors, an NHS advice service for sex workers in East London. She said her experience of the 2012 Olympic Games left her alarmed about policies in Scotland.

"An increase in enforcement, particularly in Glasgow, would be most unwelcome," she said.

"Enforcement doesn't stop people selling sex, it simply makes them go somewhere else.

"In London there were brothel raids and police enforcement on the streets, which led to huge displacement of vulnerable women. It made them far more vulnerable and our service was really struggling to find them."

The crackdown was partly predicated on a belief that major sporting events attract more sex workers to cope with an increase in demand from visitors to a city, said Ms Perry, who will speak at next week's City Health conference in Glasgow.

However this is a myth, she argues. "There is no evidence the London Olympics made a difference. The women we work with said it was quieter. Everybody was watching sport."

A blurring of the lines between sex work and human trafficking is also unhelpful, she added. "There is a conflation that says all migrant prostitutes are trafficked, but that's absolutely not the case. We see 2000 people a year and meet very few who are trafficked.

"The vast majority are quite clearly and voluntarily coming to the UK to sell sex. Many come from Romania and Brazil and go where the work is. Women go 'on tour' and Scotland is one of the places they come to work."

But this is not connected with sporting events, she argues. "The link between prostitution and trafficking has really good traction in Scotland. Women we see are vulnerable in many ways but hardly any are trafficked. Some people seem to want to broaden the definition of trafficking to raise the numbers."

Ms Perry said this was not to argue that the sex industry was a good or safe place to work. "It is clandestine, stigmatised and illegitimate. But if you try to ban things you are inevitably unsuccessful and create a much more dangerous climate.

"I am not prepared as a health professional to tolerate the collateral damage accepted by those who seek to prohibit prostitution," she added.