The paper concerns the conflict between the right to public health and the right to privacy of workers and applicants infected with the HIV virus or suffering from AIDS. Aids/Hiv specific fea-tures (i.e. standard condition of infection, lack of treatment, hight discrimination risks, etc.) justify the italian legislative choice of af-firming the prohibition of testing employees for the existence of antibodies to thís virus without their prevailing trend of banning general or limited high-risk groups compulsory screenings. The author tries to outline, on the one hand, the consequences of deci-sion n. 218/1994, through wich the italian Constitutional Court declared uncostitutional the before mentioned testing prohibition for jobs which bring with them a serious risk of ínfection. On the other hand, the essay analyses the ECJ case-law dealing with the right to privacy of HIV infectred employees (cases concerning only EC staff) and tries to compare the decisions delivered by the two Courts.