"They are always after us and we are always running or hiding away from them. Some days we get unfortunate and get caught and have to part with our cash in paying fines. Some unscrupulous officers even demand free sex in exchange of our freedom," Serite said.

One in four adults in Botswana has HIV, a rate that has hardly budged over the last decade, despite the country's relative prosperity.

Botswana doesn't track the infection rate among sex workers, but southern Africa's truck routes have long been regarded as a main pathway of the disease's spread.

"Prostitutes suffer in the hands of some clients who refuse to pay after getting the services, or who demand unprotected sex," Serite said. "It can be really tough in the streets."

Mogae, the head of the National Aids Council, argues that legalising prostitution would make it easier to help sex workers prevent the disease.

"Decriminalising sex work does not mean encouraging it, but it would rather pave way for policies that protect those who have been forced into the trade," he told a recent council meeting.

"They will be able to report men who forcibly put them at risk of contracting the virus, and in turn men who seek their services will no longer abuse them as might be the situation now," he said.

Religious groups

Legalising the sex trade would also free up police to focus on other crimes, rather than chasing adults having consensual sex with their clients, he says.

Mogae plans to bring his recommendations to cabinet and parliament.

The ruling Botswana Democratic Party, which Mogae once led, has yet to take a position on the proposal, while opposition leader Botsalo Ntuane has said he supports the move to decriminalise the 'profession'.

But his proposal has sparked a backlash among religious groups in this conservative country.

"Sex according to Christian values is meant for people in a marriage with the aim to pro-create," said the Catholic Church's spokesman Father William Horlu.

"It is taboo to engage in sex for money and I hope Botswana, being a Christian country, will not allow the trade to be decriminalised."

Mogae, who has also called for scrapping Botswana's sodomy law, retorts that religious prohibitions haven't worked.

"Italy is a Catholic country well known for prostitution. There is divorce among Muslims, though they have very strict rules. So we cannot talk about the church way because it has failed in history," he said.

The former president has won the backing of Botswana Network on Ethics, Law and HIV/Aids as well as the main opposition party.

"Criminalisation of sex work leaves sex workers vulnerable to sexual and physical abuse as well as HIV infections," said its director, Uyapo Ndadi.

"And it's not only them who will be on the receiving end, but other men who will seek their services and partners of those men. So it's a vicious circle that needs to be broken."