SOCIAL media users are expressing concerns that extreme orgies where people have unprotected sex with a mystery HIV positive person may sweeping across Europe.

In May the worrying trend of "sex roulette" parties was reported to have spread from Serbia to Spain according to a doctor in Barcelona.

2 Party goers are said to decrease their risk of contracting HIV by taking anti-viral medication

But fears seamed to have resurfaced on Twitter with one user tweeting: "'Sex roulette' parties where one person secretly has HIV are on the rise, doctors warn."

Others described it as "f****d up" while others urged kids to "just say no".

Dr Josep Mallolas of Hospital Clinic Barcelona said: “There is everything: sex roulette parties, or sex parties you can only attend if you already have HIV.”

The Spanish doctor told el Periodico that the rise of these parties meant that people had lost respect for HIV.

Most of the dangerous orgies are thought to be attended by gay men.

The reckless meetups are said to have originated in wealthy circles in Serbia where they had reportedly been popular for some time.

A stripper named only as Tijana, revealed prevalence of the unusual and and dangerous orgies in the Balkan country in 2015.

She said that the parties had been dubbed Serbian sex roulette, a play on Russian roulette.

She said: “I can see that everyone is talking about sex parties now, but in fact they have been common for a long time even here in Serbia.

"In fact what really shocked me was this bizarre variation that seems popular for extreme sex.

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"People who turn up for the party wear masks, and one of them has HIV.

“The wealthy organise these sex parties for other rich people. The real kick for these people is apparently the risk that they might be the one having sex with the HIV-infected partner.”

But this and last years just represent the latest trend in this form of risky sexual behaviour which has been known to occur for almost 20 years.

In some instances participants actively try to catch the virus, some bizarrely regarding it as either an inevitability or a badge of honour.

2 Spanish doctors warn of the rise of risky sex parties where one person secretly has HIV and condoms are banned

So called "bugchasing" is the practice of actively seeking sex with HIV positive people with the aim of contracting the disease.

Psychiatrists and psychologists have branded the disturbing behaviour as a form of self harm or even suicide.

In the bizarre vernacular of circles where this is enjoyed "bugchasers" are the negative individuals.

"Gift-givers" are the HIV positive individuals who have unprotected sex with the aim of infecting the chasers.

Behaviour at so called circuit parties can demonstrate a reckless attitude towards STI infection rather than an active desire to contract the illness.

The parties are renowned for group sex and drug taking, generally amongst gay and bisexual men which can lead to unsafe sexual practices.

According to experts it is the thrill of the unknown that drives people to take part in risky orgies.

Participants have no way of knowing if they will be infected or not in some cases and an active hope of being so in others.

But, revellers can decrease their chances of contracting the incurable virus by taking medication.

Because of this, the orgies are known as ‘blue’ parties.

Psychosexual therapist Kate Morley told HelloU: “Going to sex roulette parties is about the risk, party-goers think the higher the risk, the stronger the thrill.

“In the case of sex parties the intense high is as you combine orgasm with high adrenaline.”

What is HIV? The NHS explains: “HIV is a virus that attacks the immune system, and weakens your ability to fight infections and disease. It's most commonly caught by having sex without a condom.

“It can also be passed on by sharing infected needles and other injecting equipment, and from an HIV-positive mother to her child during pregnancy, birth and breastfeeding.

“There is no cure for HIV, but there are treatments to enable most people with the virus to live a long and healthy life.”

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