Human immunodeficiency virus type 1 incidence among blood donors in France, 1992 through 2006: use of an immunoassay to identify recent infections.
BACKGROUND
In France, blood donations found to be positive for the presence of human immunodeficiency virus type 1 (HIV-1) are further tested to detect recent infections (< or =180 days) using an enzyme immunoassay (EIA-RI) developed in 2002. The characteristics of recently infected donors, estimates of HIV-1 incidence, and the residual risk of transfusion-transmitted HIV-1 are presented, in both first-time and repeat donors.


METHODS
Of the 1027 donations found to be HIV-1-positive between 1992 and 2006, a total of 459 could be retrospectively tested with the EIA-RI. Multivariate analysis was performed to determine the donor characteristics associated with recent infection. Incidence rates and residual risk obtained with the EIA-RI were compared to classical cohort estimates derived from repeat donor histories.


RESULTS
Of the 459 HIV-1-positive donors studied, 105 (22.9%; 95% confidence interval [CI], 19.2-27.0) were identified as recently infected. Factors independently associated with recent infection were repeat donor status (adjusted odds ratio [AOR], 4.0; 95% CI, 2.4-6.9) and non-B subtypes (AOR, 2.0; 95% CI, 1.2-3.6). Incidence decreased from 4.3 (95% CI, 1.9-9.4) in 1992 through 1994 to 1.3 (95% CI, 0.6-2.8) per 10(5) in 2004 through 2006 in first-time donors and from 3.2 (95% CI, 2.0-5.0) to 0.8 (95% CI, 0.4-1.4) per 10(5) in repeat donors. Incidence and residual risk estimates were similar to those obtained with the classical cohort method.


CONCLUSIONS
This study suggests that the EIA-RI can be used to estimate HIV-1 incidence in a population with low HIV incidence. The estimated HIV-1 incidence in the blood donor population confirms the extremely low risk (1 in 3,350,000 donations) of HIV-infected blood donations entering the blood supply in France.
Pillonel
Josiane
J
Institut de Veille Sanitaire, Département des Maladies Infectieuses, Saint-Maurice, France. j.pillonel@invs.sante.fr
Barin
Francis
F
Laperche
Syria
S
Bernillon
Pascale
P
Le Vu
Stéphane
S
Brunet
Sylvie
S
Thierry
Damien
D
Desenclos
Jean-Claude
JC
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D001782:Blood Donors / Q000706:statistics & numerical data*; D015331:Cohort Studies; D005260:Female; D005602:France / Q000453:epidemiology; D015658:HIV Infections / Q000175:diagnosis* / Q000453:epidemiology* / Q000635:transmission; D015497:HIV-1 / Q000302:isolation & purification*; D006801:Humans; D007124:Immunoenzyme Techniques; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D017678:Sex Distribution