Not telling someone about a positive HIV status is criminal in my mind. Other STD’s I think ethically we should inform partners, but things like HPV for instance, a man usually does not even know he has it. I would bet many many women have had positive PAP smear, and did not understand or put together it is HPV, and still had unprotected sex with men without malice, but they are carriers. STD’s are not as clear cut as people want to think, at least not some of them. But, HIV is in a different class than the others. Although, STD’s like syphilis are deadly, and others can leave women infertile, but those are generally curable with antibiotics, so people once they know they are infected take the meds, so even though those diseases are bad, most people who pass them forward are not aware they have it. Sometimes because they are asymptomatic, and sometimes because they are stupid and don’t go to the doctor when something is wrong down there.