A retrospective analysis of the prevalence of HIV seropositivity and its demographics in the normal healthy volunteer population of a phase-I clinical drug study unit.

Abstract

A 1994 publication from the Communicable Disease Surveillance Center investigating a hepatitis B outbreak in a Phase I unit proposed that normal volunteers be routinely tested for HIV hepatitis B virus (HBV) and hepatitis C virus (HCV). The objective of this retrospective analysis was to determine the prevalence of HIV-1 and HIV-2 seropositivity and study the demographics in a Phase I drug research unit normal healthy male volunteer population. 500 heterosexual Caucasian males were screened at Guys Drug Research Unit London England as healthy volunteers for potential participation in Phase I clinical trials during the period July 1991 and September 1992. The mean age of population was 25.2 (range 19-35) years. All individuals denied behaviors compatible with a high risk of HIV transmission including drug abuse and on at least two separate occasions their urine tested negative for drugs of abuse. The Wellcome direct sandwich ELISA system was used to test for both HIV-1 and HIV-2 antibodies. All 500 subjects tested negative for both HIV-1 and HIV-2 antibodies. Demographic analysis showed that the greatest number of subjects originated from South Africa (41.8%) followed by the United Kingdom (40.6%). 318 of the 500 volunteers gave details of recent tropical travel. Africa was the most frequently visited destination followed by southeast Asia and the Indian subcontinent. 237 of the 249 subjects who travelled in Africa visited Sub-Saharan Africa the majority of these individuals originated from South Africa. 48 of the volunteers travelled to southeast Asia 29 (60.4%) visited Thailand another area where the prevalence of HIV seropositivity is high and travellers are considered to be at risk of infection. These data suggest that normal healthy male volunteer population in the absence of other risk factors intrinsically represent a low risk group for HIV seropositivity. However screening volunteers for HIV hepatitis B and C will continue and it is suggested that other units conducting similar drug studies consider such a policy.