Predictors of Early and Late Mother-to-Child Transmission of HIV in a Breastfeeding Population: HIV Network for Prevention Trials 012 Experience, Kampala, Uganda

Makerere University-Johns Hopkins University Research Collaboration, Kampala, Uganda.
JAIDS Journal of Acquired Immune Deficiency Syndromes (Impact Factor: 4.56). 08/2009; 52(1):32-9. DOI: 10.1097/QAI.0b013e3181afd352
Source: PubMed


To determine the predictors for early versus later (breastfeeding) transmission of HIV-1.
Secondary data analysis was performed on HIV Network for Prevention Trials 012, a completed randomized clinical trial assessing the relative efficacy of nevirapine (NVP) versus zidovudine in reducing mother-to-child transmission (MTCT) of HIV-1. We used Cox regression analysis to assess risk factors for MTCT. The ViroSeq HIV genotyping and a sensitive point mutation assay were used to detect NVP resistance mutations.
In this subset analyses, 122 of 610 infants were HIV infected, of whom 99 (81.1%) were infected early (first positive polymerase chain reaction < or =56 days). Incidence of MTCT after 56 days was low [0.7% per month (95% confidence interval, CI: 0.4 to 1.0)], but continued through 18 months. In multivariate analyses, early MTCT "factors" included NVP versus zidovudine (hazard ratio (HR) = 0.57, 95% CI: 0.38 to 0.86), pre-entry maternal viral load (VL, HR = 1.76, 95% CI: 1.28 to 2.41), and CD4 cell count (HR = 1.16, 95% CI: 1.05 to 1.28). Maternal VL (6-8 weeks) was associated with late MTCT (HR = 3.66, 95% CI: 1.78 to 7.50), whereas maternal NVP resistance (6-8 weeks) was not.
Maternal VL was the best predictor of both early and late transmission. Maternal NVP resistance at 6-8 weeks did not predict late transmission.

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    • "HIV-infected individuals who maintain increased levels of HIV-1 RNA load, extended high viremics, can transmit virus at higher rates. Combinatorial ART decreases HIV replication, thus reducing rates of virus transmission [35,36]. "
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    ABSTRACT: Background: Three decades since the first HIV-1 infected patients in Rwanda were identified in 1983; the Acquired Immunodeficiency Syndrome epidemic has had a devastating history and is still a major public health challenge in the country. This study was aimed at assessing socioeconomic, clinical and biological risk factors for mother - to - child transmission of HIV- in Muhima health centre (Kigali/Rwanda). Methods: The prospective cohort study was conducted at Muhima Health centre (Kigali/Rwanda).During the study period (May 2007 - April 2010), of 8,669 pregnant women who attended antenatal visits and screened for HIV-1, 736 tested HIV-1 positive and among them 700 were eligible study participants. Hemoglobin, CD4 count and viral load tests were performed for participant mothers and HIV-1 testing using DNA PCR technique for infants.Follow up data for eligible mother-infant pairs were obtained from women themselves and log books in Muhima health centre and maternity, using a structured questionnaire.Predictors of mother-to-child transmission of HIV-1 were assessed by multivariable logistic regression analysis. Results: Among the 679 exposed and followed-up infants, HIV-1 status was significantly associated with disclosure of HIV status to partner both at 6 weeks of age (non-disclosure of HIV status, adjusted odds ratio [AOR] 4.68, CI 1.39 to 15.77, p < 0.05; compared to disclosure) and at 6 months of age (non-disclosure of HIV status, AOR, 3.41, CI 1.09 to 10.65, p < 0.05, compared to disclosure).A significant association between mother's viral load (HIV-1 RNA) and infant HIV-1 status was found both at 6 weeks of age (> = 1000 copies/ml, AOR 7.30, CI 2.65 to 20.08, p < 0.01, compared to <1000 copies/ml) and at 6 months of age (> = 1000 copies/ml, AOR 4.60, CI 1.84 to 11.49, p < 0.01, compared to <1000 copies/ml). Conclusion: In this study, the most relevant factors independently associated with increased risk of mother - to - child transmission of HIV-1 included non-disclosure of HIV status to partner and high HIV-1 RNA. Members of this cohort also showed socioeconomic inequalities, with unmarried status carrying higher risk of undisclosed HIV status. The monitoring of maternal HIV-1 RNA level might be considered as a routinely used test to assess the risk of transmission with the goal of achieving viral suppression as critical for elimination of pediatric HIV, particularly in breastfeeding populations.
    Archives of Public Health 02/2013; 71(1):4. DOI:10.1186/0778-7367-71-4
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    • "Although factors associated with MTCT have been quantified [7]–[10], the mechanisms underlying postnatal transmission remain poorly understood, in particular the relative roles of cell-free (RNA) and cell-associated (DNA) HIV-1 in breastmilk transmission. High levels of cell-free virus in maternal plasma and breastmilk are associated with a high risk of HIV-1 transmission during breastfeeding [11]–[16]. "
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    PLoS ONE 12/2012; 7(12):e51493. DOI:10.1371/journal.pone.0051493 · 3.23 Impact Factor
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    • "Each 0.5 log10 increment in HIV-1 RNA level may lead to a 40% greater risk of heterosexual transmission [10]. Studies focusing on mother-to-child-transmission (MTCT) demonstrate that levels of plasma viral RNA load [11], [12], [13] in HIV-infected mothers are the best predictors of viral transmission. Individuals with primary or late-stage HIV infection are highly infectious [14], [15] due to increased levels of viral RNA load. "
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    PLoS ONE 04/2010; 5(4):e10148. DOI:10.1371/journal.pone.0010148 · 3.23 Impact Factor
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