HIV seroconverting donors delay their return: screening test implications.
BACKGROUND
The yield of HIV p24 antigen testing implemented in March 1996 has been lower than projected. One possible explanation is that HIV seroconverting donors delay their return because of the recent practice of risk behaviors and/or signs and symptoms associated with primary infection.


METHODS
From a database of 6.8-million allogeneic donations collected at five U.S. blood centers from 1991 to 1997, 49 HIV, 21 HCV, 32 HTLV, and 44 HBsAg seroconverters with at least three donations were identified. A statistical method was developed to investigate whether the time between a donor's last negative donation and their positive donation was significantly longer than expected based on their previous return history.


RESULTS
HIV seroconverters returned on average 42 percent later than expected (p < 0.01). Although not significant, HCV seroconverters donated on average 43 percent earlier than expected. HTLV and HBsAg seroconverters did not appear to change their donation pattern around the time of seroconversion. Sixty-three percent of the HIV seroconverters later acknowledged practicing a high-risk behavior.


CONCLUSIONS
HIV seroconverters delay their return around the time of seroconversion and are thus less likely to be recently infected. Unique among HIV seroconverters, this observation provides a possible explanation for the lower than expected yield of HIV p24 antigen testing and suggests that NAT may have a similar low yield.
Schreiber
George B
GB
Westat, Rockville, Maryland, USA. georgeschreiber@westat.com
Glynn
Simone A
SA
Satten
Glen A
GA
Kong
Fanhui
F
Wright
David
D
Busch
Michael P
MP
Tu
Yongling
Y
Kleinman
Steven H
SH
D001782:Blood Donors; D015480:Deltaretrovirus Antibodies / Q000097:blood; D016655:HIV Core Protein p24 / Q000276:immunology; D006679:HIV Seropositivity; D016174:Hepacivirus / Q000276:immunology; D006510:Hepatitis B Antibodies / Q000097:blood; D006514:Hepatitis B Surface Antigens / Q000276:immunology; D006526:Hepatitis C / Q000821:virology; D018937:Hepatitis C Antibodies / Q000097:blood; D006801:Humans; D012307:Risk Factors; D012725:Sexual Behavior; D013997:Time Factors
D015480:Deltaretrovirus Antibodies; D016655:HIV Core Protein p24; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D018937:Hepatitis C Antibodies