A national review of vertical HIV transmission.
OBJECTIVE
Prevention of vertical HIV transmission has evolved significantly in Canada over the last two decades. The aim of this analysis is to describe the surveillance programme used, rate of vertical HIV transmission and changing epidemiology of HIV-affected pregnancies in Canada.


METHODS
National perinatal HIV surveillance programme.


METHODS
From 1990, annual retrospective data was collected on demographic and clinical characteristics of HIV-infected mothers and their infants referred to 22 participating sites across Canada either before/during pregnancy or within 3 months after delivery. Factors impacting HIV transmission and demographic features were explored.


RESULTS
Two thousand, six hundred and ninety-two mother-infant pairs were identified. The overall rate of vertical HIV transmission was 5.2%, declining to 2.9% since 1997. The rate of transmission for mothers who received HAART was 1%, and 0.4% if more than 4 weeks of HAART was given. Forty percent of women delivered by caesarean section, with no difference in transmission rate compared with vaginal delivery for women treated with HAART (1.4 vs. 0.6%, P = 0.129) but significant risk reduction for those who did not receive HAART (3.8 vs. 10.3%, P = 0.016). Black women were the largest group; proportions of black and aboriginal women increased significantly over time (P < 0.001 for both). Heterosexual contact was the most common risk category for maternal infection (65%), followed by injection drug use (IDU) (25%).


CONCLUSIONS
Vertical HIV transmission in Canada has decreased dramatically for women treated with HAART therapy. All pregnant women should be evaluated for HIV infection and programmes expanded to reach vulnerable populations including aboriginal, immigrant and IDU women.
Department of Pediatrics, University of British Columbia, Vancouver, Canada.
John C
JC
Forbes
Ariane M
AM
Alimenti
Joel
J
Singer
Jason C
JC
Brophy
Ari
A
Bitnun
Lindy M
LM
Samson
Deborah M
DM
Money
Terry C K
TC
Lee
Normand D
ND
Lapointe
Stanley E
SE
Read
D023241:Antiretroviral Therapy, Highly Active; D002170:Canada / Q000453:epidemiology; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000635:transmission*; D006801:Humans; D007223:Infant; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control / Q000706:statistics & numerical data*; D011159:Population Surveillance / Q000379:methods*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors