True HIV seroprevalence in Indian blood donors

The National AIDS Control Organization (NACO), the apex body for controlling AIDS in India, projected that HIV seroprevalence would increase from 7/1000 in 1995 to 21.2/1000 in 1997. A high incidence (8.2%) of HIV was observed in blood donors. This study was carried out to find out the true HIV positivity in Indian blood donors. Blood donors from our centre were followed for more than 5 years to determine the true HIV seroprevalence and our result was compared with similar studies from India. Voluntary and relative blood donors who visited the SGPGIMS, Lucknow, since 1993 to June 1998 were included. They were screened for HIV 1/2 by ELISA kits (WHO approved). First-time HIV-positive samples were preserved frozen for further study (stage-I). They were repeated in duplicate and retested with other kits. If found positive, the sample was labelled as ELISA positive (stage-II). ELISA-positive samples were confirmed by Western Blot (WB) at stage-III. A total of 65 288 donors were included and 834 (12.8/1000) were reactive at stage-I. But 1.1/1000 donors were found to be ELISA positive at stage-II, and 0.28/1000 donors were positive by WB at stage-III. The 'seropositivity' rate from the NACO was significantly (P < 0.001) higher than our study. There were five similar Indian studies and seropositivity rate varied from 0.72/1000 (using ELISA and WB) to 5.5/1000 (using ELISA alone). The 'seropositivity' rate from the NACO was significantly (P < 0.001) higher than all these studies. HIV seroprevalence in the present study is lower (P < 0.001) than other Indian figures. The present and other studies confirmed that the projected HIV seroprevalence (82/1000) in Indian blood donors was high. The NACO result was based on one-time ELISA screening reports from zonal blood testing centres which also receive samples from paid donors donating in commercial blood banks. The HIV prevalence of blood donors (and national prevalence) is to be reassessed.