Page 333 - SAHCS HIVMed Journal Vol 20 No 1 2019

Page 2 of 7 Original Research

Annual studies reporting on MTCT in infants ≤ 1500 g from Study population
2005 to 2007 noted HIV transmission rates of 14.9%, 19.0% The study population was identified from ward registers.
13
12
and 10.0%, respectively. At this time, the implementation of The start of this study, 01 March 2010, coincided with the
14
ART for PMTCT in South Africa was inconsistently applied implementation of the National 2010 PMTCT guideline.
(Table 1). Subsequently (2008–2015), MTCT declined from Records of patients admitted to the unit in the subsequent 36
7.6% to 0.0% 15,16,17 when PMTCT became the standard of care consecutive months were audited. Breast milk was prescribed
(Table 1). This included improved infant regimens at and to all infants admitted to the neonatal unit and supplemented
post-delivery 18,19,22,23,24 and the provision of maternal by DBM if MOM was insufficient.
combination ART (cART) to pregnant and breastfeeding
women. No infants included in these studies (n = 289) Infants were included if they were HIV-exposed, that is, born
23
received rMOM from birth. 15,16,17 to an HIV-positive mother and received prMOM, that is, at
least two-thirds of the total enteral volume, over the study
Most HIV-exposed preterm infants prior to initiation of period. The remaining one-third enteral fluid volume was
modern PMTCT programmes received EFF, as did their DBM and was given with infant antiretroviral prophylaxis.
term counterparts. 18,19 Subsequently, the safety of heat- The latter was daily nevirapine from birth until at least 6 weeks
treated expressed MOM was confirmed, 20,21 and this became of age. A surveillance HIV-PCR was checked at 6 weeks as per
the feeding choice for hospitalised preterm infants in many the 2010 National PMTCT programme. 19,22 (Table 2).
facilities. Although affordable, 20,21 heat-treated MOM is
labour-intensive in a hospital setting and for mothers Deviations from the surveillance regimen 19,22 were indicated
after discharge. Also, it remained unclear whether in some infants. These included HIV-PCR testing at ‘non-
non-HIV-related benefits of MOM were lost through the routine’ times, for example, within 72 h after birth to diagnose
heat treatment. congenital infection; before 6 weeks of age in the event of
clinical signs suggestive of HIV infection; and should
Study objective discharge occur before 4 weeks of age to minimise the
number who might not return and so be lost to follow-up. All
A retrospective, observational audit was undertaken to HIV-PCR test results were accessed from patient files and the
determine the cumulative incidence of peripartum HIV National Health Laboratory Service (NHLS) database.
transmission at 4–6 weeks of age in HIV-exposed VLBW
infants, who received infant prophylaxis according to the Definitions
National PMTCT programme of 2010 19,22 and ‘predominantly’
raw MOM (prMOM) (see Study Population section for the Congenital infection
definition of prMOM). In utero acquisition of HIV (congenital infection) was diagnosed
when an HIV-PCR was positive within 72 h of birth.
Material and methods
Setting Peripartum infection
The MTCT of HIV during the peripartum period was defined
This study was performed in the Neonatal Unit of Kalafong as HIV acquisition during labour, delivery or while receiving
Provincial Tertiary Hospital, South Africa. The neonatal unit prMOM and nevirapine (NVP) prophylaxis. It was diagnosed
comprises 30 beds, which include 6 neonatal intensive care when an HIV-PCR test was negative within 72 h after birth
beds. There are approximately 5900 deliveries per year at yet positive at 4–6 weeks. In the absence of an early HIV-PCR,
Kalafong Provincial Tertiary Hospital, with a maternal HIV peripartum infection was excluded if the HIV-PCR was
prevalence of approximately 18%. negative at 4–6 weeks.

TABLE 1: South African studies reporting on human immunodeficiency virus transmission by postnatal age in infants ≤ 1500 g birth weight.
Year Hospital Birth weight (n) Maternal ART Infant regimen Infant feeding MTCT of HIV
2003–2005 < 1500 g sdNVP during labour or AZT from 34 weeks sdNVP or sdNVP+AZT: 99% Heat-treated EBM/DBM/EFF 14.9% by 14 weeks
Tygerberg 12 (141) gestation with sdNVP during labour: 72%
2006–2007 < 1500 g cART: 1% sdNVP: 73% Not documented 19% by 6 weeks
Chris Hani Baragwanath 13 (26) NVP before delivery: 36% (95% CI: 7% – 40%)
2006–2007 ≤ 1500 g sdNVP: 37% sdNVP: 100% Heat-treated EBM/EFF 10% by 6 weeks
Kalafong 14 (83) cART: 13%
No ART: 50%
2007–2008 ≤ 1500 g cART: 17% AZT: 100% Heat-treated EBM/DBM/EFF 7.6% by ≥ 2 weeks
Tygerberg 15 (185) AZT/NVP before delivery: 28%
AZT/NVP during labour: 43%
No ART: 15%
2010–2011 ≤ 1000 g Some ART: 72% NVP or sdNVP+AZT: 100% Heat-treated EBM/DBM/EFF 2.7% by 6 weeks
Groote Schuur 16 (37) (ART >1 month before delivery: 44%) (95% CI: 0.7% –14.1%)
2014–2015 < 1500 g ART >1 month before delivery: 72% NVP+AZT: 100% Heat-treated EBM until infant 0% by 6 weeks
Groote Schuur and New (67)† ART <1 month before delivery: 9% can breastfeed/DBM/
Somerset 17 No ART: 13% EFF
ART, antiretroviral therapy; AZT, azidothymidine; DBM, donor breast milk; EFF, exclusive formula feeding; cART, combination antiretroviral therapy; NVP, nevirapine; sdNVP, single dose nevirapine;
PCR, polymerase chain reaction; EBM, expressed breast milk.
†, Number of infants calculated from the statement by the authors that 87% of the cohort that was negative at birth (n = 77) was tested at 6 weeks of age.

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