Abstracts Vol. 1 [International Conference on AIDS (11th: 1996: Vancouver, Canada)]

Tu.C.2578 - Tu.C.2582

Tuesday July 9, 1996

Objective: To determine the prevalence of HIV infections in women attending antenatal
clinic' in The Gambia, and to determine the rates of, and maternal risk factors for, motherto- child tr ansmission of these infections.
Methods: From January 1993 to March 1995 we screened 29,670 women attending the
eight iargest antenatal clinics in the country. Seropositive mothers were matched for age,
paity and health centre w th seroneg iat ve controls. A cinician visits the mothers and their
Sbabies it tw o, nine and e ig teenmonths af ter birth, when blood samples are taken from
the babies forimmunologica and wr-oloical studies. 254 HIV-2 seropostive pregnant
women were examined by a study clinician and blood samples taken for FACscan and PCR
anal is. For detection of HIV 2 pr ovrus, nested PCR was carried out with HIV-2 specific
LTR primers.
Results: We identified 492 HIV infected women (I.7%).The prevalence of HIV I and HIV-2
infections among the screened women was 0.5% and 1.1 % respectively, and 0.05% of the
woraen were found to be dually reactive. HIV 2 positive women were significantly older
(mein 27.8 years) than HIV I positive women (mean 23.6 years, p<0.01).The mean percentage CD4 counts were significantly lower in HIV I positive women (36.6%) than in HIV2 positive women (44.5%, p<0.05)), whose counts were lower than those of seronegative
controls. HIV 2 signal has been detected by PCR in 109 of I 7 (93.2%) HIV 2 seropositive
mothers. 150 children of HIV2 seropositive women have so far been followed successfully
at 2 months and 9 months of age for investigation of HIV-2 infection. PCR analysis of samples taken fromr 9 month old babies of 94 HIV 2 PCR positive women shows that five cases
of mother to child transmission have taken place in this group (rate 5.3%). Mothers who
transmit tend to be symptomatic, but only one had an antenatal CD% count <29%.
Quantitative analysis of viral load is underway
Conclusions: Motherto child transmission of HIV 2 is not uncommon, although it remains
to be c arified which of these transmission events occurred in the postnatal period.
Diarrnuid O'Donovan, MRC Laboratories, P O Box 273, Banjul,The Gambia Telephone: +
220 195444 Fax: + 220 495919 email.:[email protected]
Tu.C.2578
QC-PCR QUANTITATION OF HIV-I PLASMA RNA LEVEL DURING PREGNANCY:A
NEW PROGNOSTIC MARKER FOR VERTICAL TRANSMISSION
Lutz-Friedrich Renate*, Grubert TA*, Dathe O", Stauber M*, Notheis G**,Wintergerst
U*, Solder B*, Belohrads<y BH**, Eberle J**, Gurtler L***. Ludwig-MaximiliansUniversitdt, *I. Frauenklinik, *Immundefektambulanz, ***Max von Pettenkofer Institut,
Munich, Germany
Objective: To determine the role of viral burden of the pregnant women, measured by
quantitative competitive - PCR (QC PCR) quantitation of RNA plasma levels for the vertical transmission of HIV-I.
Methods: In a cohort of 4 I HIV posit e women we monitored CD4-cell counts, p24 antigen levels and the possibility of virus isolation by cell culture during pregnancy. 8 children of
these women were infected (8/4 19,5 %) We were able to quantitate retrospectively
maternal plasma HIV-I RNA levels by QC -RT RNA-PCR (Fa. Roche) in the blood of 6
mothers of infected children.We compared the results with a control group of HIV positive
mothers of healthy childrer, matched by maternal CDC-status and CD4-cell counts. In a
seconrd, stil ongoing study we used the serial quantitation of maternal RNA plasma levels as
monitoring for AZT efficiac in pregnancy in correlation with CD4-cell counts, p24 antigen
and vertical transmission rate.
Results: We observed correlations between p24 antigen and RNA plasma levels as well as
CD4-cell counts and RNA plasma levels, but none of them correlated statistically significant.
The RNA plasma levels of the transmitting mothers in comparison to the non transmitting
control group did not allow to define a transmission threshold. Especially in African women
the nreasured RNA plasma levels were exceedingly low, which might indicate that particular
HIV subtypes other than B are not suficiently identifed by the applied method.
Conclusions: Up to now we cannot find a well defined limit of RNA plasma level as a
threshold for vertical transmission. [he quantitation of RNA plasma levels was strongly
biased bt the HIV subtype, suggesting that especially African HIV subtypes might not be
sufficiently detected by the applied QC-PCR-method.
R.Lutz Friedrich, i.Frauenkhnik der LMU, Maistrasse I I, D-80337 Munich Phone: ++49-89 -5 I 60 4704 Fax + [phone] emai:[email protected]
Tu.C.2579
MOTHER-TO-INFANT TRANSMISSION OF HIV-I IN SOUTH AFRICA
Lyons, Susan F.*, Bredell, W.J.*, McGilivray G.M.*,Whistler,T*, Gray G.-*, McIntyre, J.A.*.
*MRC AIDS Virus Research Unit, National Institute forVirology Johannesburg; uPerinatal
HIV Pesearch Unit, Baragwniath Hospital, University of the Witwatersrand, Johannesburg,
South Africa
Objective: To determine the local mother to-child (M-to-C) transmission rate of HIV I and
identify factors influencng tr ansmssion.
Methods: A long -term, prospective study, initiated in 1993, assessed the HIV- I infection status of infants using the polymerase chain reaction (PCR) assay with env, vif and gag primers,
and b ELISA for HIV- I-spe:ific antibodies. Children with either (a) at least 2 of 3 primer
pairs pasitive hy PCR oc 2,orecutve spec mens or (b) HIV I antibody positive beyond
I 8 mionths of age, were idenatifled ar DIV- infected.
Results: Of the 320 mother infant pars enrolled in the study appropriate follow-up specimens were received feom l68 infirnts, of which 59 were HIV i infected, to establish an
overall local M-to-C transmission rate for HIV I of 35. 1%.Two infants, PCR-positive at 6
weeks of age, seroreverted. Two further infants, PCR negative at 4 and 12 months of age
respectively became PCR positive on follow up; both had been breastfed.
Data on the mother's CD4+ count at the time of delivery method of feeding and mode of
delivery were obtained fom 02 of the mother-infant parsAmongst this sub-group the
tirasrson raite was 42.2?( with 43 of the rnfants becoming infected. An inverse correlation was observed between CD4+ cell counts and transmission rates, with intants born to
mothers with depressed counts at higher risk of infection. Breast feeding also increased the
risk of transmission of HIV-I with 37 of 76 (48.7%) breastfed infants acquiring the infection
whIle only 6 of 26 (23.I%) formula fed infants became infected. Mode of delivery also influenced the transmission rate with different rates observed for normal vaginal delivery elective, and emergency Caesaran sections.

Conclusions: The M-to-C rate in South Afica is similar to tht seo n other Ai
tries although it may have been skewed upward by the possibilt that won er
matic children would be more likely to return to the chnic for redcal cre.e
CD4+ count at the time of delivery, method of feeding and mode aof Veral
the transmission rate.The data also demonstrate that seroreversir - r ts b
seropositive mothers does not preclude HIV infection.

-.f I -,r-.

Sus ar F Lyons, Privaite Bag X4, San drirlham 2 I 3 South Afri-,el i.8 9i
Fax:(011 ) 882-0596,e-mail: sueloivac.za
Tu.C.2580
VERTICAL TRANSMISSION OF HIV IS CORRELATED WITH A HIGH MATERNAL
VIRAL LOAD AT DELIVERY
Coll O*, Hernandez M", Boucher C"i, Fortuny C*, Canet Espanol T. Ma tin-Ter r
B* iHospital Clinic Barcelona, Spain, "*Cuitat Sanitarna Vall d 'Hebro BKit,,eloa. 5sp,
**University of Amsterdam, Holland.
Objective: To determine the factors that contribute to vertical transmiss -on of HIV I nd tc
develop and evaluate strategies to decrease the rate of transmission.
Methods: We studied a group of 67 HIV infected mothers and the irh9 nee -, n(2 ci
of twins) from 2 hospitals in Barcelona (Hospital Clinic and Clutat init, V ii!d'Hei b,
to seropositive mothers does not preclude HIV infection.
cal care.The mothers lent epidemiological, clinical and laboratory nfoi i )iti or ii- the
mothers and blood samples at delivery -he mean age of the mothes wa 26.3 i
Forty nine (73%) acquired the rinfection through IV drug use and 18 (27%) thre, sex
contact.The mean gestational age at delivery was 38. 4+ 2.4 wee s. Dinoi, p Se r
in children was based on persistence of anti-HIV-I antibodies at 1 8 months of a i
tive HIV I culture or PCR in two separate samples or presence of sign or symptoms
AIDS before 18 months of age.
Results: Seventeen (24%) children (including a set of twins) were diagnosed as IV
infected.The mode of acquisition of the mother's infection, the gestiatro ie itdehvery
and the mode of delivery were not associated with the rate of transmsson. A hlt r etionship was observed between the transmission rate in relator to:. a CDC tae IV o
infection ( 1/69, odd ratio 8.4.95% CI 1.6 45.2, p=0.00 1). CD4 counts at del.ver 00
cell/ml (27/69, odds ratio 4.1; 95% CI: I. I-15.4, p=0.0 I), presence of p24 antigen (569
odds ratio 5.36, 95% CI 2.1 -139) and most significantly with a high number of vil RNA
copies (>105) in the mothers serum (15/69, odds ratio 22.0; 95% CI.t1- 119, p<0.000 )
Conclusion: HIV- I vertical transmission is strongly associated wc th)h a hih maternl i
viral RNA load at delivery.Viral load which is related to clinicl and mrunoloyica ttsof
the mother is the main contributing factor for HIV I vertical transminssion.These findings
may have global and individual therapeutic implications.
0. Coll, C/ Sabinoe Arana 50, 10~ 2", Barcelona 08028, Spain Telephone: 31-4 1I 2583. FAX:
343-41 1-2583
Tu.C.258 I
CHILDREN BORN TO HIV-I AND HCV COINFECTED MOTHERS
Sarinchez, Emilia*, Fortuny Cc*, Ercilla MG**, Sorni A-I, Jime nez R ". * feath Pi Irn:r
Area. Catalan Health Service. Generalitat de Catalunya. Y"Integrated Pediatric- Unit.
Dept. Immunology Hospital Cirnic and Sant Joan de Deu. University of Barcelona Barcelon,
Spain.
Objective: To study the epidemiology of vertical transmission of HIV I and HV ichldre
born to coinfected mothers.
Methods: All infants born to both HIV I and HCV coInfected womenw eedt
Hospital Clinic i Provincial in Barcelona, from I/I/1987 to 2/28/ 1993 were sccted.( no
and laboratory follow-up was scheduled at birth and every month thcrrer tl the hId
was 18 month old, and included physical examination and ELISA HIV, El ISA H iWete n
blot, p24 antigenemia, viral coculture, RIBA and PCR assas, swell is aninotiirIfe ii M
surements.
Results: 130 infants born to 120 HIV I and HCV coinfected women were derntfi ed. Mot
of these women were current or formner IVDU (1 17) and only acquired he ifect n
through sexual intercourse with IVDU men. After- a mean follow up period of}4.4i month
6 children were lost.Transmission rates were estimated to be 3.7 (714) HIV,
13.7% (17/124) for HCV and 4.8% (6/124) for both viruses simultaneously. HCV nfectcn
was confirmed in 35.3% of HIV- I -infected children and in 10.I3% of seror-cver-ters
(OR=4.76, p-0.01). Case-fatality rate was 4.0% (5/1214); all deat a, in coifeter
children who also met AIDS criteria.
Conclusions: Children born to mothers coinfected by both HIV I and HCV seem to have:
I) a lower probability of becoming HIV I-infected than those born to mothers inected by
HIV I alone; 2) a higher risk of becoming HCV-infected when HIV I infection,ai pro
sent.

Emilia Sanchez. Area Sanitaria. Servei Catal de la Salut.Trav. de es
Barcelona, Spain. Phone: [phone] Fax: [phone]

08028

Tu.C.2582
VERTICAL TRANSMISSION OF HIV INFECTION IN NEWBORN:A PRELIMINARY
REPORT
U ij itaroon Y-2, Barusrux S1,2, Romphruk A2, Puapa roj C2, Lumbganon P3 TaksapS
Dept.Clin.lmm., Fac. AMS; 2Blood Transfusion Center, Fac. MED: 3Dept. Pediatric. Fac. ME[
KKU, Khon Kaen,Thailand.
Objective: To investigate HIV infection in infants born to HIV I seropositve mother.
Methods: Blood samples were collected frhom infants born to HIV I seroposit e aother
withine 48 hours after delivery durin g January to December 1995 e n S ri nari nd ospt.1i
Northeastern,Thailand. HIV p24 antigen was detected by ELISA (Couiter- HII,/i p ovi-al
DNA for gag region was performed by nested PCR assay
Results: Blood samples were available from 25 neonates. None of them demonstrra e i
itive for HIV p24 antigen. HIV I proviral DNA was detected in on ly one infnt fio l who
the blood sample was collected 24 hours after birth. Further test ng in subsequent blood
samples and clinical follow up has been on going for diagnosis of HIV ver t ic
in these infants.

365