Exposure to HIV-1 during delivery and mother-to-child transmission.
BACKGROUND
The correlation between the presence of HIV-1 in maternal cervicovaginal secretions and in the infant's oro-pharyngal secretions at birth, and mother-to-child HIV transmission (MTCT) were examined to obtain a better understanding of its mechanism.


METHODS
Women without medical and obstetrical complications, living within a reasonable distance of the government hospital in Mombasa, Kenya, were recruited after informed consent. Maternal and infant characteristics were collected. Polymerase chain reaction was used to detect HIV-1 in cervico-vaginal and oro-pharyngal secretions. Infants were tested for HIV-1 by polymerase chain reaction within 48 h and at 6 weeks after delivery.


RESULTS
Between April 1998 and April 1999, 228 woman-infant pairs were included in the study. HIV-1 DNA in cervico-vaginal secretions was independently associated with HIV-1 maternal viral load and with infant birth-weight, whereas HIV-1 RNA was associated with maternal viral load and maternal age. HIV-1 DNA in the oropharyngal secretions was also independently associated with maternal viral load. MTCT rate at the age of 6 weeks was 23.6%. Intrapartum and early postpartum HIV transmission was independently associated with maternal viral load [adjusted odds ratio (OR), 1.6; 95% confidence interval (CI),1.0-2.7], detection of HIV-1 RNA in cervico-vaginal secretions (adjusted OR, 3.2; 95% CI, 1.5-7.3) and of HIV-1 DNA in oro-pharyngeal secretions (adjusted OR, 3.2; 95% CI, 1.1-9.0).


CONCLUSIONS
As far as is known, this is the first study showing that infant exposure to HIV-1 in the birth canal and the presence of HIV-infected cells in the infant's oropharyngeal cavity are independently associated with intrapartum and early postpartum MTCT. It supports the hypothesis that MTCT could occur through the oral route.
Gaillard
P
P
International Centre for Reproductive Health, University of Ghent, Belgium.
Verhofstede
C
C
Mwanyumba
F
F
Claeys
P
P
Chohan
V
V
Mandaliya
K
K
Bwayo
J
J
Plum
J
J
Temmerman
M
M
D012634:Bodily Secretions / Q000821:virology; D015331:Cohort Studies; D005260:Female; D005836:Genitalia, Female / Q000821:virology; D015658:HIV Infections / Q000635:transmission*; D015497:HIV-1; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D007630:Kenya; D009960:Oropharynx / Q000821:virology; D016133:Polymerase Chain Reaction; D017201:Virus Shedding