In 19 US states, it is law that somebody with HIV has to disclose it to a sexual partner. However, during the initial dating stage, there is nothing that says a person has to disclose that they are HIV positive. If you suspect that something is not as it seems with a partner, ask them outright because honesty should be the base for any healthy relationship. Many people are scared potential love interests will have some kind of disease and not tell them, so this is the reason why there are such dating sites around like Positive Singles. You know exactly what you are getting right from the start.