Foreigners with a known HIV infection or who are living with AIDS are not subject to specific residence regulations.
Foreigners who come to work in Switzerland for the first time are subject to the regulations about sanitary measures at the border (...). No HIV testing is performed during this examination. EU and EFTA nationals are not subject to this medical examination anyway (the screening is mainly performed to recognise cases of tuberculosis).
Applicants for asylum are not tested for HIV on entry either. However, the medical examination mentioned above is performed on them.
(Source: 1)
Antiretroviral medication can be imported for personal use. It is recommended to carry a prescription.
(Source: 2)