Is it ethical for HIV positive doctors to disclose this patients?

Did you mean disclose their status to patients or diagnose patients.

I have no problem with a HIV positive DR treating me. I think it should be up to the DR to decide if they want to disclose their status. Knowing the DR's status won't affect me in any way. I don't need to know if they are married or own a house, so their HIV status isn't any more relevant.

I dont think it has anything to do with ethics. I believe physicians would put themselves out of a job if they let that kind of info out of the bag.
If my physician disclosed he was HIV positive, it would be my choice and It probably would not make a difference to me.

The results of a positive HIV test, is given ONLY to the patient, never to third parties, or the doctor will face the risk of a legal complain, for breech of confidentiality.
The result has to be discussed (once it has been confirmed beyond doubt) to the patient only, in private,,,,however, if he or she brings along somebody else, (spouse, parent, brother etc) you an assume that the patient has given the consent for the other person to know the result too.
Never results are given by letter or by phone, or by fax etc. (nobody does that) and if surely positive, the result is given verbally and showing the lab test (proof) by appointment only.
Never otherwise.
It is always ethical to disclose the results to the patient....If not,,,,why were they performed,? and by the request of whom? in the first place.
A different case is the patient that never shows up to know the results....it is ethical not to disclose the results to anybody else, however. anonymous (no name of the patient) is made to the epidemiological control of the State where the physician pratices....