Human Rights Watch on Thursday called on the Greek government to repeal a regulation forcing suspected sex workers and other groups to undergo HIV testing, reintroduced last week by the country's newly appointed health minister.

"It's deeply worrying that it took the new health minister only one day to bring back a regulation that violated human rights and stigmatised vulnerable groups, and that proved counterproductive to protecting public health," Judith Sunderland, senior Western Europe researcher at the New York-based rights group, said in a statement.

Adonis Georgiadis, who became health minister after a government reshuffle last week, brought back a regulation that allows authorities to detain people and run tests for HIV and other diseases.

It was originally passed in April 2012 but recalled a year later.

The regulation was used to target suspected sex workers, undocumented migrants and drug users, Human Rights Watch said.

Georgiadis, a former member of extreme right party Laos, joined conservative Prime Minister Antonis Samaras's New Democracy last year.

In May 2012, Amnesty International called on the Greek government to end a campaign stigmatising HIV-positive prostitutes.

The prominent human rights organisation's call came after a scandal involving a young Russian prostitute found to be HIV positive, which led to the detention of many sex workers.

Prostitution is legal in Greece, as long as it is carried out in brothels, which, at least in theory, have strict regulations.

According to Greece's centre for disease control and prevention (Keelpno), HIV infections have been on the rise in the country since 2000.

"In all, 1,180 cases of HIV infection were reported in 2012 (10.9 cases per 100,000 population), which is the highest figure ever recorded in the HIV/AIDS reporting system," the organisation said.

On Wednesday, gay rights group Homophonia-Thessaloniki Pride organised a protest against the reintroduction of the regulation.

On its website, the group said the bill "violates human rights and medical confidentiality."