"Looking for men and women for no-strings attached sex, preferably no condoms?" reads the enticingly explicit message seemingly posted by a young Brazilian woman on meet-up mobile site Tinder.

In reality, though, the poster is not a sultry Brazilian redhead. Rather, the message has been sent by the ministry of health as part of an in-your-face AIDS prevention campaign.

Anybody responding to the invitation purportedly sent by "Alana" gets not a hot date but a phone screen warning message reading: "Attention, it is difficult to know who is an AIDS carrier. Enjoy yourself - but take care. This is a campaign by the ministry of health."

With AIDS rates on the increase among Brazilian youngsters the government decided to launch its campaign using the Tinder and Hornet phone applications.

"Augusto," on Hornet, boasts: "Sex without shame, sex with no limits. I like unprotected sex."

Health Minister Arthur Chioro explained in launching the initiative that "we can no longer talk about at-risk groups."

"Anyone who has a sex life is vulnerable, hence the importance of using a condom and undergoing testing," he added in a speech Monday.