RESUMEN
In an examination of 109,041 subjects for the presence of antibodies to HIV in the serum in 7 cases a positive result was obtained by the EIA method (Abbott), including 2 blood donors (out of 101,971 examined ones), 4 homosexuals (of 232 ones) and 1 prostitute (of 337 ones). All results were confirmed by the Western blot technique in the State Institute of Hygiene in Warsaw. Three out of six men infected with HIV had had previously syphilis. No positive result was found in 2420 foreign students at the universities in Lódz. In the group of blood donors, besides the above mentioned 2 cases of certain HIV infection, in another 8 cases difficulties were encountered in the interpretation of the results indicating the need for further serological observation.