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

12th World AIDS Conference

Abstracts 23270-23274 395

Results: Of 1073 children with complete information, 864 (81%) received ZDV
antenatally, perinatally, or neonatally; 568 (53%) received full 076 Rx. The most
common reasons for mothers who were diagnosed with HIV before delivery to not
receive ZDV antenatally were no prenatal care (26%) or refusal of ZDV (21%).
Among 494 known HIV-exposed children who received full 076 Rx, 43 (9%) were
infected with HIV, compared with 14 of 48 (29%) who received no ZDV (RR = 0.3,
Cl 0.2-0.5). PCP prophylaxis was started by 2 months of age for 497 (46%) of
the children studied. The primary reason for not starting PCP prophylaxis was the
practice of not starting uninfected children on prophylaxis (66%). Of all children
who started prophylaxis, 14 (3%) stopped due to a drug reaction; among 150
HIV-infected children, 5/139 (4%) who started PCP prophylaxis and 4/11 (36%)
who did not were diagnosed with PCP (RR = 0.1, Cl 0.04-0.43).
Conclusions: This study of approximately 1/6 of the total number of HIVexposed children born in the US in 1995 indicates that most received at least one
component of full 076 Rx, but only 53% received full 076 Rx. Despite receiving
recommended 076 Rx and PCP prevention, some children were diagnosed with
HIV and PCP. More attention to prevention failures and barriers, such as lack of
prenatal care, is needed.
457*/23270 HIV infection due to breastfeeding in a cohort of
babies not infected at enrollment
Taha Taha1, P. Miotti2, N. Kumwenda3, H. Van Der Hoeven3, D. Markakis3,
D. Hoover3, R. Biggar4. 1615 North Wolfe Street, Suite #E6011 Baltimore,
Maryland 21205; 2National Institute of Health Bethesda MD; 3Johns Hopkins
University Baltimore MD; 4NCI National Institute Health Bethesda MD, USA
Objectives: To determine the rate and timing of HIV infection due to breast feeding in a cohort of babies who tested HIV negative by polymersae chain reaction
(PCR) at or immediately after birth.
Methods: Babies born to HIV positive mothers were PCR tested in a large birth
canal cleansing intervention trial in Malawi. Children with negative PCR results
were enrolled in a longitudinal study after counseling the mother and obtaining
consent. Follow-up visits were scheduled every 3 months to collect information
on risk factors, and every 6 months to obtain a heel-prick blood sample on filter
paper for PCR testing. ELISA and Western blot tests were done at 15 months and
every three months thereafter. PCR conversion/sero-conversion was defined as
a change from last negative to first positive HIV test result. Survival analysis was
used to estimate hazard and cumulative incidence based on an interval censoring
weighted analysis.
Results: 621 HIV negative babies were enrolled. During a median follow-up
of 32 months, 47 conversions were first detected between 8 and 18 weeks
(estimated incidence of 3.5%), 11 were first detected between 19 and 60 weeks
(estimated incidence of 1.9%) and 23 were first detected after 60 weeks (estimated incidence of 3.8%). At enrollment, 98% of the converters and 97% of the
non-converters were breast-fed. None of the babies who converted had blood
transfusion. Other risk factors such as cracked nipples and swelling of the breasts
were infrequent. 42 conversions which occurred between birth and 7 weeks are
not included in the above estimates since the majority of these conversions could
have been due to intrapartum factors.
Conclusion: In this population, the HIV transmission rate due to breastfeeding
is at least 9.2%. This risk needs to be compared with expected morbidity and
mortality resulting from not breastfeeding.
232711 Trends in prevalence of HIV among childbearing women
in California, USA: 1998 through 1995
Juan Ruiz1, D. Zukowski1, J. Mikanda1, C. Tempelis2, C. Cossen2. 1California
Dept. of Health Services, 830 S Street, Sacramento; 2Berkeley, CA, USA
Objectives: To assess trends in HIV prevalence in childbearing women in California from 1988 to 1995 and estimate the annual incidence of perinatal HIV
infection in California.
Methods: In an anonymous, population-based serosurvey, over 1,150,000
specimens collected from newborns in California were tested for maternal HIV
antibody between July-September from 1988 to 1995. The survey used newborn
blood specimens and maternal demographic information originally collected for
routine metabolic screening. Analyses by survey period and race/ethnic group
in selected regions were performed. Assuming a 25% transmission rate, we
estimated the annual incidence of perinatal HIV infection in newborns.
Results: From 1988 through 1995, the estimated HIV prevalence among
childbearing women in California remained relatively stable at approximately 0.7
per 1,000 live births, with no significant trend. In all survey years and regions,
black childbearing women had the highest prevalence. Comparing survey periods 1988-91 and 1992-95, the prevalence increased among black women in San
Francisco, San Diego, and non-urban regions; increased among Latina women in
every region except San Francisco; and decreased among white women in every
region except Los Angeles. The estimated incidence of HIV-infected childbearing
women delivering live born infants in California ranged from a low of 322 in 1993
to a high of 488 in 1991. The estimated incidence of perinatal HIV infection ranged

from a low of 81 in 1993 to a high of 108 in 1990.
Conclusion: Overall HIV prevalence among childbearing women in California
remained stable from 1988 to 1995. The increase in HIV prevalence among black
and Latina women, especially in non-urban areas, is troublesome because a large
percentage of these women could be unaware of being at risk for HIV infection.
Prevention and care programs must continue to address the problem of perinatal
transmission.

23272 1 Decreased perinatal HIV-1 transmission following elective
cesarean delivery with zidovudine treatment
Laurent Mandelbrot1, J. Le Chenadec2, A. Berrebi3, A. Bongain4, J.L. Benifla5,
J.F. Delfraissy6, M.J. Mayaux2. 1Service De Gynecologie-Obstetrique 123 Bd.
De Port-Royal 75014 Paris; 2INSERM U292, Kremlin-Bicetre; 3Hopital La Grave,
Tolouse; 4Hopital L'Archet 2, Nice; 5Hopital Bichat, Paris; 6Hopital Kremlin
Bicetre, Kremlin-Bicetre, France
Background: Whether cesarean section may be a method to prevent perinatal
HIV transmission is controversial, and has not yet been studied in the presence
of zidovudine prevention.
Methods: The French Perinatal Cohort followed 2834 singleton infants born to
HIV-1 infected mothers from 1985 to 1996, with known infection status.
Results: Among 1917 mothers who did not receive zidovudine, 17.2 percent transmitted HIV-1 to their infant. Risk factors significantly associated with
transmission were: maternal p24 antigenemia, cervicovaginal infections during
pregnancy, amniotic fluid color, and rupture of membranes >4 hours. Mode of
delivery was not related to transmission. Among 902 mothers receiving zidovudine, transmission was 6.4 percent. Elective cesareans (n = 133) were associated
with a lower transmission rate than emergent cesareans or vaginal deliveries (0.8
percent, 11.4 percent, and 6.6 percent, respectively; P < 0.002). In a multivariate
analysis, the factors related to transmission rate were maternal p24 antigenemia,
amniotic fluid color and elective cesarean, versus vaginal delivery (adjusted odds
ratio = 0.10; 95 percent confidence interval: 0.00 to 0.9; P < 0.04).
Conclusions: There was an interaction between zidovudine treatment and
elective cesarean section in reducing perinatal HIV-1 transmission. This may offer
insight into the mechanisms of perinatal transmission, as well as those of antiretroviral prophylaxis. Clinical implications for prevention should be considered.
458*/23273 Missed opportunities to reduce perinatal HIV
transmission: Maternal and neonatal zidovudine
(ZDV) use in Los Angeles County (LAC)
Toni Frederick1, Laurene Mascola1, J. Jackson1, Y.S. Shin1, A. Kovacs2,
J. Bertolli3. Pediatrics AIDS Consortium, Los Angeles, CA; 1Los Angeles County
Department of Services, 313 N Figueroa Street, Rm 203, Los Angeles;
2LAC-USC Medical Center, Los Angeles, CA; 3Centers for Disease
Control/Prevention, Atlanta GA, USA
Background: In 1994, results of ACTG 076 showed that ZDV given to HIV+
pregnant woman prenatally, during labor and delivery (L&D) and subsequently to
the newborn for 6 weeks could significantly reduce HIV vertical transmission. In
LAC, it is now standard of care to follow the 076 regimen. We examined maternal
and neonatal ZDV (NZDV) use for HIV-exposed children born in '95-96.
Methods: Pediatric HIV surveillance began in LAC in 1988 as part of CDC's
Pediatric Spectrum of Disease (PSD) Study. Nurses identify new children through
routine visits to all medical centers in LAC that treat HIV-infected and exposed
children. Maternal and neonatal ZDV data are collected at baseline from pediatric
hospital and clinic charts and reflect what is recorded in this record. Unknown
data were excluded from the denominators.
Results: As of 10/97, 223 perinatally exposed infants born in 1995-96 were
reported to PSD; 84% were identified at birth. 76% (148/195) of mother's received
ZDV during pregnancy, 72% (136/190) during L&D, and 78% (174/223) received
NZDV. Of those with complete ZDV data on all three 076 treatment arms, 84%
(151/179) received at least one intervention and 116 (65%) received all three
arms. Of the 223 infants, 160 (72%) of the mothers had prenatal care, 20 (9%)
did not, and for 44 (20%) data were unknown. Of the 160 with prenatal care, 149
(93%) were known to be HIV+ at the child's birth. Those with prenatal care, 90%
(133/147) received ZDV during pregnancy, 82% (122/148) in L&D, 89% (143/160)
got NZDV, and 62% (111/140) received all three; 93% recceived at least one
intervention compared to 53% (34/63) of those with unknown or no prenatal care
(RR = 6.8, 95% CI = 3.5, 12.8). Race was not associated with prenatal care or
ZDV during pregnancy. While not statiscally significant, whites were more likely
than non-whites to receive ZDV during L&D (RR = 2.9, 95% CI, 0.8, 11.1) and
receive NZDV (OR = 2.0, 95% CI, 0.9, 4.4).
Conclusions: Failure to receive prenatal care, and/or failure to complete all
three 076 treatment arms, have created a significant number of missed opportunities for maternal and infant ZDV. Prevention efforts must continue to focus
not only on offering pregnant women HIV testing, but developing interventions to
keep them and their babies, particularly among non-whites, in treatment.
|23274 A "Bloodless cesarean section" and perinatal
transmission of the human immunodeficiency virus
Audra Deveikis1, C.V. Towers1, T. Asrat1, C. Major1, M.P. Nageotte2. 1Memorial
Miller Children's Hospital, Long Beach, CA; 2Memorial Womens Hospital, Long
Beach, CA, USA
Backgroun: A prospective cohort study in HIV infected pregnant women to
evaluate the rate of transmission of HIV to the neonate based on the mode of

delivery.
Methods: One group of patients was delivered by means of a "Bloodless
Cesarean Section" (BCS) where the baby was delivered and not exposed to
macroscopic maternal blood or bodily fluid. The control group gave birth either
by vaginal delivery or routine Cesarean section. All of the newborns were followed for a minimum of 15 months or until confirmed negative. Multiple antenatal,
intrapartum, and post delivery variables were collected and analyzed.