Bridging the Gap: Conference Record [Abstract book, International Conference on AIDS (12th: 1998: Geneva, Switzerland)]

396 Abstracts 23275-23278

12th World AIDS Conference

Results: 108 patients participated, 14 neonates became infected with HIV
(13%). 3 of 53 infants delivered by a BCS (5.7%) became infected compared to
11 of 55 control patients (20.0%). This was significant at p =.02 and represented
an absolute difference in percentage between the 2 groups of 14.3% or a 71.5%
relative reduction in transmission risk (z = 2.27, p = 0.012). Since the use of
zidovudine greatly impacts the perinatal transmission rate of HIV, the study data
were reanalyzed excluding patients who used antenatal or intrapartum zidovudine. Two of 32 infants in the BCS group (6.3%) were infected compared to 9 out
of 38 in the control group (23.7%). This was significant at p =.04 and revealed an
absolute difference in percentage of 17.4% which corresponds to a 73.4% relative
reduction in transmission risk (z = 2.15, p = 0.016). There was no difference in
the transmission rate between the BCS patients who did not use zidovudine (2
out of 32 or 6.3%) compared to patients who did use zidovudine from the entire
study population (3 out of 38 or 7.9%).
Conclusion: In absence of zidovudine usage, these data show that 70% to
75% of the perinatal transmission of HIV to a newborn occurs from exposure to
maternal blood and bodily fluids at the time of birth. This information is important
for patients unable to take zidovudine or other anti-retroviral agents but more
importantly it introduces the concept of other treatment options for the future.
23275 1 Mode of delivery and vertical transmission of HIV-1:
A meta-analysis from fifteen prospective cohort studies
(the International Perinatal HIV Group)
Jennifer Read. PAMA Branch, NICHD, Executive Bldg, Rm 4B11F, MSC 7510,
NIH, Bethesda, MD, USA
Background: Since a large proportion of vertical transmission of HIV-1 (HIV)
appears to occur during the intrapartum period and transmission is associated
with intrapartum factors, obstetrical management of the HIV-infected pregnant
woman may affect the risk of transmission. The goal of this study is to evaluate
the relationship between mode of delivery and vertical transmission of HIV in a
meta-analysis utilizing individual patient data from prospective studies.
Methods: The a priori hypothesis is that HIV-infected women undergoing elective cesarean section have a lower risk of transmission of HIV to their infants
compared to those with other modes of delivery. This meta-analysis offers significant advantages as compared to previous studies: uniform definitions of four
categories of mode of delivery applied across all studies [elective (before rupture
of membranes, before onset of labor) and non-elective cesarean section, and
instrumented (with forceps and/or vacuum suction) and non-instrumented vaginal
delivery] and multivariate analyses incorporating important covariates. Eligible
studies for inclusion in this meta-analysis were European and North American
studies of at least 100 mother-child pairs with prospective data collection regarding
mode of delivery and HIV infection status of the child.
Results: Fifteen prospective cohort studies were identified, and data regarding
10,729 mother-child pairs are available for analysis. Deliveries occurred from
1982 to 1996, inclusive. Of 8229 vaginal deliveries, 630 (8%) were instrumented.
Of 2500 cesarean sections, 1046 (42%) were elective. The overall transmission
rate was 14%.
Conclusions: The large sample size available should provide adequate power
for detection of at least a 20% decreased risk of vertical transmission of HIV with
elective cesarean section as compared to other modes of delivery. This metaanalysis, including multivariate analyses incorporating data regarding receipt of
antiretroviral therapy, maternal AIDS, maternal CD4+ lymphocyte counts, and
other important covariates, will be completed by June 1998.
528*/23276 A randomized trial of STD control during
pregnancy in Rakai, Uganda: Impact on maternal
and infant health
Ronald H. Gray1, G. Kingozi2, F. Wabwire-Mangen2, D.S. Serwadda3, C. Li1,
M. Meehan4, M.J. Wawer1. 1Johns Hopkins University, 615 N. Wolfe St,.
Baltimore Md. 21205; 4Columbia University, New York NY USA; 2Makerere
University, Kampala; 3Mulago Hospital, Kampala, Uganda
Objectives: To evaluate effects of mass STD treatment on pregnancy outcome
and maternal-infant infections.
Design: Prospective, community-based, single-blinded, randomized trial of
STD control
Methods: In a randomized trial of STD Control for AIDS Prevention, pregnant women are enrolled into a maternal-infant follow up study. Single oral
regimens are provided once during pregnancy: intervention arm women receive
azithromycin, cefixime and metronidazole, and control arm receive iron/folate.
Syphilis is treated with IM penicillin in both arms. Data are collected in the home
during pregnancy and postpartum, and include interviews, HIV and syphilis serology, urinary LCR for gonorrhea (GC) and chlamydia (Ct), vaginal swabs for BV
(gram stain) and trichomoniasis (Tv) culture, clinical exam for upper genital tract
infection (UGTI), and placental histopathology. Infant low birthweight (LBW) is
based on anthropometry, diagnosis of ophthalmia is by conjunctival LCR and HIV
by PCR. Analyses examine rates (%) and relative risks (RR) in intervention vs

control arm, using statistical tests adjusted for cluster randomization.
Results: Between 1995-97 we enrolled 3635 pregnant women (1818 Intervention, 1817 Control) and 2973 mothers/infants (1576 Intervention, 1397 Control).
Compliance was >90%.

Results are as follows:
Maternal: Tv BV GC Ct UGTI Infant: GC Ct LBW Mortality
Intervention (%) 5.7 37.6 0.9 1.1 2.2 0.6 0.8 9.8 4.6
Control (%) 17.3 52.4 2.1 3.6 3.6 1.5 1.3 12.6 4.7
RR (p < 0.05*) 0.30 0.72 0.43 0.31 0.61 0.40 0.60 0.78 0.98
Data on STD infection, chorioamnionitis and mother-to-child HIV transmission will be available
shortly.
Conclusions: Mass treatment of STDs in pregnant women is feasible and
results in substantial reductions of maternal and infant morbidity.
23277 Placenta infection in HIV-1 transmission in utero
Bruno M. Polliotti, A.U. Sheikh, K. Craig, R.K. Miller. Univ. of Rochester - Dept.
OB/GYN 601 Elmwood Ave - Rochester, NY 14642, USA
Objective: Factors involved in the transmission of HIV-1 in utero include viral load
and viral genotype in the maternal circulation; however, the role of the placenta
in this process remains unclear. The aim of this study is to determine if HIV-1
transmission in utero can occur without placental infection.
Methods: Prospective (10 patients) and retrospective (4 patients) cases of
HIV-1 positive pregnancies were investigated for in utero transmission and HIV-1
infection of the placenta. In utero infection was determined by the baby infection
within 8 days of life using independent determinations. The infectious status of the
mother and baby were assessed clinically and verified at birth when blood was
available using polymerase chain reaction (PCR) from peripheral blood mononuclear cells (PBMC). Localization of viral DNA was performed by using in situ PCR
(ISPCR) for gag, pol and LTR regions. The average gestational age at delivery
was 38.5 ~ 1.5 weeks and the average birth weight 3100 ~ 500 g. In this study,
the race ratio was 69% Black, 23% Hispanic and 8% White.
Results: In the non-transmitted babies cases, with negative DNA PCR cord
blood determination, the placentae appeared to have positive ISPCR for HIV-1
in maternal PBMC. In all cases of babies infected in utero, we identified infected
syncytiotrophoblast, Hofbauer and stromal cells in the placenta by ISPCR.
Conclusion: In this interim study, placental infection was identified by ISPCR
in each case of in utero transmission, and never when the baby was not infected.
This study is ongoing in attempt to collect as large number of case before further
generalization, however, these results support the concept that placenta must be
first infected before the fetus can be infected by HIV-1 in utero.
S23278 The Thai Red Cross donation campaign to prevent
mother- to-child transmission of HIV
Praphan Phanuphak1, U. Thisyakorn2, S. Sirivichayakul3, S. Nukhai1,
V. Pradubgaew1, C. Kunanusont4, W. Poolchareon4. 'Program on AIDS, Thai
Red Cross Society, 1871 Rama IV road, Bangkok 10330; 2Dept. Pedriatrics,
Chulalongkorn Hospital, Bangkok; 3Dept. Medicine, Chulalongkorn Univ Hosp,
Bangkok; 4AIDS Division CDC, Ministry of Health, Nonthaburi, Thailand
Issue: Many resource-poor countries are uncertain about the acceptance, feasibility and sustainability of the use of zidovudine (ZDV) in the prevention of
mother -to-child transmission of HIV. While waiting for government's decision and
action, governmental organizations can lend their supports by launching some
demonstration projects to test its acceptance and feasibility.
Project: Thai Red Cross Society (TRCS), with the support of Princess Soamsawali and the Ministry of Public Health (MOPH), initiated a donation campaign
to procure ZDV for poor pregnant women throughout Thailand in order to test
its acceptance and feasibility. The treatment regimen of ACTG 076 was followed
except that during labor, intravenous ZDV was replaced by oral ZDV 300 mg
given 3-hourly. Any hospitals with interested obstetricians, pediatricians and with
adequate supporting infrastructure could request free ZDV from TRCS for their
eligible patients.
Results: From February 1996 to December 1997, a total of US$ 273,538 donation has been collected. In addition, MOPH has provided US$ 80,000 worth ZDV
to the project. Distribution of ZDV started in June 1996. By the end of December
1997, a total of 1,393 pregnant women from 63 hospitals throughout Thailand
have received ZDV from TRCS and 798 babies have been born. Preliminary
analysis of dried blood spots by nested PCR from 241 babies collected 8 days to
8 months after birth revealed a transmission rate of 5.4% as compared to 25-30%
in untreated cohorts. Evaluation of the operation in 4 hospitals with largest number
of patients showed that treatment was completed in over 95% of patients and
follow-up rate of the newborns was over 90%. The success depended heavily on
the commitment of the hospital staffs and the good infrastructure set up for this
intervention.
Lessons Learned: This ongoing campaign demonstrates that there are adequate public supports and there are demands both from the hospitals and the
patients and that treatment is indeed effective in the Thai setting. The success
will encourage the MOPH to build up the infrastructure of other hospitals and to
prepare the budget for nationwide implementation. This example of multisectorial

collaboration, i.e., the Royal Family, TRCS, MOPH, hospitals and the public to
save a child's life from AIDS will give a good working model for other developing
countries to follow.