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JAMA | 2010

Coverage of Nevirapine-Based Services to Prevent Mother-to-Child HIV Transmission in 4 African Countries

Elizabeth M. Stringer; Didier K. Ekouevi; David Coetzee; Pius M. Tih; Tracy Creek; Kathryn Stinson; Mark J. Giganti; Thomas Welty; Namwinga Chintu; Benjamin H. Chi; Catherine M. Wilfert; Nathan Shaffer; François Dabis; Jeffrey S. A. Stringer

CONTEXTnFew studies have objectively evaluated the coverage of services to prevent transmission of human immunodeficiency virus (HIV) from mother to child.nnnOBJECTIVEnTo measure the coverage of services to prevent mother-to-child HIV transmission in 4 African countries.nnnDESIGN, SETTING, AND PATIENTSnCross-sectional surveillance study of mother-infant pairs using umbilical cord blood samples collected between June 10, 2007, and October 30, 2008, from 43 randomly selected facilities (grouped as 25 service clusters) providing delivery services in Cameroon, Côte dIvoire, South Africa, and Zambia. All sites used at least single-dose nevirapine to prevent mother-to-child HIV transmission and some sites used additional prophylaxis drugs.nnnMAIN OUTCOME MEASUREnPopulation nevirapine coverage, defined as the proportion of HIV-exposed infants in the sample with both maternal nevirapine ingestion (confirmed by cord blood chromatography) and infant nevirapine ingestion (confirmed by direct observation).nnnRESULTSnA total of 27,893 cord blood specimens were tested, of which 3324 were HIV seropositive (12%). Complete data for cord blood nevirapine results were available on 3196 HIV-seropositive mother-infant pairs. Nevirapine coverage varied significantly by site (range: 0%-82%). Adjusted for country, the overall coverage estimate was 51% (95% confidence interval [CI], 49%-53%). In multivariable analysis, failed coverage of nevirapine-based services was significantly associated with maternal age younger than 20 years (adjusted odds ratio [AOR], 1.44; 95% CI, 1.18-1.76) and maternal age between 20 and 25 years (AOR, 1.28; 95% CI, 1.07-1.54) vs maternal age of older than 30 years; 1 or fewer antenatal care visits (AOR, 2.91; 95% CI, 2.40-3.54), 2 or 3 antenatal care visits (AOR, 1.93; 95% CI, 1.60-2.33), and 4 or 5 antenatal care visits (AOR, 1.56; 95% CI, 1.34-1.80) vs 6 or more antenatal care visits; vaginal delivery (AOR, 1.22; 95% CI, 1.03-1.44) vs cesarean delivery; and infant birth weight of less than 2500 g (AOR, 1.34; 95% CI, 1.11-1.62) vs birth weight of 3500 g or greater.nnnCONCLUSIONnIn this random sampling of sites with services to prevent mother-to-child HIV transmission, only 51% of HIV-exposed infants received the minimal regimen of single-dose nevirapine.


Tropical Medicine & International Health | 2012

Universal voluntary HIV testing in antenatal care settings: a review of the contribution of provider‐initiated testing & counselling

Bernadette Hensen; Rachel Baggaley; Vincent Wong; Kristina L. Grabbe; Nathan Shaffer; Ying-Ru Jacqueline Lo; James Hargreaves

Objectiveu2002 To assess the contribution of provider‐initiated testing and counselling (PITC) to achieving universal testing of pregnant women and, from available data on components of PITC, assess whether PITC adoption adheres to pre‐test information, post‐test counselling procedures and linkage to treatment.


PLOS ONE | 2013

Cost-Effectiveness Analysis of Option B+ for HIV Prevention and Treatment of Mothers and Children in Malawi

Olufunke Fasawe; Carlos Avila; Nathan Shaffer; Erik Schouten; Frank Chimbwandira; David Hoos; Olive Nakakeeto; Paul De Lay

Background The Ministry of Health in Malawi is implementing a pragmatic and innovative approach for the management of all HIV-infected pregnant women, termed Option B+, which consists of providing life-long antiretroviral treatment, regardless of their CD4 count or clinical stage. Our objective was to determine if Option B+ represents a cost-effective option. Methods A decision model simulates the disease progression of a cohort of HIV-infected pregnant women receiving prophylaxis and antiretroviral therapy, and estimates the number of paediatric infections averted and maternal life years gained over a ten-year time horizon. We assess the cost-effectiveness from the Ministry of Health perspective while taking into account the practical realities of implementing ART services in Malawi. Results If implemented as recommended by the World Health Organization, options A, B and B+ are equivalent in preventing new infant infections, yielding cost effectiveness ratios between US


Journal of Epidemiology and Community Health | 2015

First population-level effectiveness evaluation of a national programme to prevent HIV transmission from mother to child, South Africa

Ameena Ebrahim Goga; Thu-Ha Dinh; Debra Jackson; Carl Lombard; Kevin P. Delaney; Adrian Puren; Gayle G. Sherman; Selamawit A. Woldesenbet; Vundli Ramokolo; Siobhan Crowley; Tanya Doherty; Mickey Chopra; Nathan Shaffer; Yogan Pillay

37 and US


PLOS ONE | 2015

Missed opportunities along the prevention of mother-to-child transmission services cascade in South Africa : uptake, determinants, and attributable risk (the SAPMTCTE)

Selamawit A. Woldesenbet; Debra Jackson; Carl Lombard; Thu-Ha Dinh; Adrian Puren; Gayle G. Sherman; Vundli Ramokolo; Tanya Doherty; Mary Mogashoa; Sanjana Bhardwaj; Mickey Chopra; Nathan Shaffer; Yogan Pillay; Ameena Ebrahim Goga; South African Pmtct Evaluation (Sapmcte) Team

69 per disability adjusted life year averted in children. However, when the three options are compared to the current practice, the provision of antiretroviral therapy to all mothers (Option B+) not only prevents infant infections, but also improves the ten-year survival in mothers more than four-fold. This translates into saving more than 250,000 maternal life years, as compared to mothers receiving only Option A or B, with savings of 153,000 and 172,000 life years respectively. Option B+ also yields favourable incremental cost effectiveness ratios (ICER) of US


PLOS ONE | 2012

Health facility characteristics and their relationship to coverage of PMTCT of HIV services across four African countries: the PEARL study.

Didier K. Ekouevi; Elizabeth M. Stringer; David Coetzee; Pius M. Tih; Tracy Creek; Kathryn Stinson; Andrew O. Westfall; Thomas Welty; Namwinga Chintu; Benjamin H. Chi; Cathy Wilfert; Nathan Shaffer; Jeff Stringer; François Dabis

455 per life year gained over the current practice. Conclusion In Malawi, Option B+ represents a favorable policy option from a cost-effectiveness perspective to prevent future infant infections, save mothers lives and reduce orphanhood. Although Option B+ would require more financial resources initially, it would save societal resources in the long-term and represents a strategic option to simplify and integrate HIV services into maternal, newborn and child health programmes.


PLOS ONE | 2015

Impact of Maternal HIV Seroconversion during Pregnancy on Early Mother to Child Transmission of HIV (MTCT) Measured at 4-8 Weeks Postpartum in South Africa 2011-2012: A National Population-Based Evaluation

Thu-Ha Dinh; Kevin P. Delaney; Ameena Ebrahim Goga; Debra Jackson; Carl Lombard; Selamawit A. Woldesenbet; Mary Mogashoa; Yogan Pillay; Nathan Shaffer

Background There is a paucity of data on the national population-level effectiveness of preventing mother-to-child transmission (PMTCT) programmes in high-HIV-prevalence, resource-limited settings. We assessed national PMTCT impact in South Africa (SA), 2010. Methods A facility-based survey was conducted using a stratified multistage, cluster sampling design. A nationally representative sample of 10u2005178 infants aged 4–8u2005weeks was recruited from 565 clinics. Data collection included caregiver interviews, record reviews and infant dried blood spots to identify HIV-exposed infants (HEI) and HIV-infected infants. During analysis, self-reported antiretroviral (ARV) use was categorised: 1a: triple ARV treatment; 1b: azidothymidine >10u2005weeks; 2a: azidothymidine ≤10u2005weeks; 2b: incomplete ARV prophylaxis; 3a: no antenatal ARV and 3b: missing ARV information. Findings were adjusted for non-response, survey design and weighted for live-birth distributions. Results Nationally, 32% of live infants were HEI; early mother-to-child transmission (MTCT) was 3.5% (95% CI 2.9% to 4.1%). In total 29.4% HEI were born to mothers on triple ARV treatment (category 1a) 55.6% on prophylaxis (1b, 2a, 2b), 9.5% received no antenatal ARV (3a) and 5.5% had missing ARV information (3b). Controlling for other factors groups, 1b and 2a had similar MTCT to 1a (Ref; adjusted OR (AOR) for 1b, 0.98, 0.52 to 1.83; and 2a, 1.31, 0.69 to 2.48). MTCT was higher in group 2b (AOR 3.68, 1.69 to 7.97). Within group 3a, early MTCT was highest among breastfeeding mothers 11.50% (4.67% to 18.33%) for exclusive breast feeding, 11.90% (7.45% to 16.35%) for mixed breast feeding, and 3.45% (0.53% to 6.35%) for no breast feeding). Antiretroviral therapy or >10u2005weeks prophylaxis negated this difference (MTCT 3.94%, 1.98% to 5.90%; 2.07%, 0.55% to 3.60% and 2.11%, 1.28% to 2.95%, respectively). Conclusions SA, a high-HIV-prevalence middle income country achieved <5% MTCT by 4–8u2005weeks post partum. The long-term impact on PMTCT on HIV-free survival needs urgent assessment.


AIDS | 2014

Adoption of national recommendations related to use of antiretroviral therapy before and shortly following the launch of the 2013 WHO consolidated guidelines.

Nelson Lj; Beusenberg M; Habiyambere; Nathan Shaffer; Marco Vitoria; Montero Rg; Philippa Easterbrook; Meg Doherty

Objectives We examined uptake of prevention of mother-to-child HIV transmission (PMTCT) services, predictors of missed opportunities, and infant HIV transmission attributable to missed opportunities along the PMTCT cascade across South Africa. Methods A cross-sectional survey was conducted among 4–8 week old infants receiving first immunisations in 580 nationally representative public health facilities in 2010. This included maternal interviews and testing infants’ dried blood spots for HIV. A weighted analysis was performed to assess uptake of antenatal and perinatal PMTCT services along the PMTCT cascade (namely: maternal HIV testing, CD4 count test/result, and receiving maternal and infant antiretroviral treatment) and predictors of dropout. The population attributable fraction associated with dropouts at each service point are estimated. Results Of 9,803 mothers included, 31.7% were HIV-positive as identified by reactive infant antibody tests. Of these 80.4% received some form of maternal and infant antiretroviral treatment. More than a third (34.9%) of mothers dropped out from one or more steps in the PMTCT service cascade. In a multivariable analysis, the following characteristics were associated with increased dropout from the PMTCT cascade: adolescent (<20 years) mothers, low socioeconomic score, low education level, primiparous mothers, delayed first antenatal visit, homebirth, and non-disclosure of HIV status. Adolescent mothers were twice (adjusted odds ratio: 2.2, 95% confidence interval: 1.5–3.3) as likely to be unaware of their HIV-positive status and had a significantly higher rate (85.2%) of unplanned pregnancies compared to adults aged ≥20 years (55.5%, p = 0.0001). A third (33.8%) of infant HIV infections were attributable to dropout in one or more steps in the cascade. Conclusion A third of transmissions attributable to missed opportunities of PMTCT services can be prevented by optimizing the uptake of PMTCT services. Identified risk factors for low PMTCT service uptake should be addressed through health facility and community-level interventions, including raising awareness, promoting women education, adolescent focused interventions, and strengthening linkages/referral-system between communities and health facilities.


Aids Care-psychological and Socio-medical Aspects of Aids\/hiv | 2013

Maximizing the impact of HIV prevention efforts: Interventions for couples

Amy Medley; Rachel Baggaley; Pamela Bachanas; Myron S. Cohen; Nathan Shaffer; Ying Ru Lo

Background Health facility characteristics associated with effective prevention of mother-to-child transmission of HIV (PMTCT) coverage in sub-Saharan are poorly understood. Methodology/Principal Findings We conducted surveys in health facilities with active PMTCT services in Cameroon, Cote dIvoire, South Africa, and Zambia. Data was compiled via direct observation and exit interviews. We constructed composite scores to describe provision of PMTCT services across seven topical areas: antenatal quality, PMTCT quality, supplies available, patient satisfaction, patient understanding of medication, and infrastructure quality. Pearson correlations and Generalized Estimating Equations (GEE) to account for clustering of facilities within countries were used to evaluate the relationship between the composite scores, total time of visit and select individual variables with PMTCT coverage among women delivering. Between July 2008 and May 2009, we collected data from 32 facilities; 78% were managed by the government health system. An opt-out approach for HIV testing was used in 100% of facilities in Zambia, 63% in Cameroon, and none in Côte dIvoire or South Africa. Using Pearson correlations, PMTCT coverage (median of 55%, (IQR: 33–68) was correlated with PMTCT quality score (rhou200a=u200a0.51; pu200a=u200a0.003); infrastructure quality score (rhou200a=u200a0.43; pu200a=u200a0.017); time spent at clinic (rhou200a=u200a0.47; pu200a=u200a0.013); patient understanding of medications score (rhou200a=u200a0.51; pu200a=u200a0.006); and patient satisfaction quality score (rhou200a=u200a0.38; pu200a=u200a0.031). PMTCT coverage was marginally correlated with the antenatal quality score (rhou200a=u200a0.304; pu200a=u200a0.091). Using GEE adjustment for clustering, the, antenatal quality score became more strongly associated with PMTCT coverage (p<0.001) and the PMTCT quality score and patient understanding of medications remained marginally significant. Conclusions/Results We observed a positive relationship between an antenatal quality score and PMTCT coverage but did not identify a consistent set of variables that predicted PMTCT coverage.


PLOS Medicine | 2013

Measuring Coverage in MNCH: Population HIV-Free Survival among Children under Two Years of Age in Four African Countries

Jeffrey S. A. Stringer; Kathryn Stinson; Pius M. Tih; Mark J. Giganti; Didier K. Ekouevi; Tracy Creek; Thomas Welty; Benjamin H. Chi; Catherine M. Wilfert; Nathan Shaffer; Elizabeth M. Stringer; François Dabis; David Coetzee

Background Mother-to-child transmission of HIV (MTCT) depends on the timing of HIV infection. We estimated HIV-seroconversion during pregnancy (HSP) after having a HIV-negative result antenatally, and its contribution to early MTCT in South Africa (SA). Methods and Findings Between August 2011 and March 2012, we recruited a nationally representative sample of mother-infant pairs with infants aged 4-to-8 weeks from 578 health facilities. Data collection included mother interviews, child health-card reviews, and infant dried-blood-spots sample (iDBS). iDBS were tested for HIV antibodies and HIV-deoxyribonucleic-acid (HIV-DNA). HSP was defined as maternal self-report of an HIV-negative test during this pregnancy, no documented use of antiretroviral drugs and a matched HIV sero-positive iDBS. We used 20 imputations from a uniform distribution for time from reported antenatal HIV-negative result to delivery to estimate time of HSP. Early MTCT was defined based on detection of HIV-DNA in iDBS. Estimates were adjusted for clustering, nonresponse, and weighted by SA’s 2011 live-births. Results Of 9802 mother-infant pairs, 2738 iDBS were HIV sero-positive, including 212 HSP, resulting in a nationally weighted estimate of 3.3% HSP (95% Confidence Interval: 2.8%-3.8%). Median time of HIV-seroconversion was 32.8weeks gestation;28.3% (19.7%- 36.9%) estimated to be >36 weeks. Early MTCT was 10.7% for HSP (6.2%-16.8%) vs. 2.2% (1.7%-2.8%) for mothers with known HIV-positive status. Although they represent 2.2% of all mothers and 6.7% of HIV-infected mothers, HSP accounted for 26% of early MTCT. Multivariable analysis indicated the highest risk for HSP was among women who knew the baby’s father was HIV-infected (adjusted-hazard ratio (aHR) 4.71; 1.49-14.99), or who had been screened for tuberculosis (aHR 1.82; 1.43-2.32). Conclusions HSP risk is high and contributes significantly to early MTCT. Identification of HSP by repeat-testing at 32 weeks gestation, during labor, 6 weeks postpartum, in tuberculosis-exposed women, and in discordant couples might reduce MTCT.

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Elizabeth M. Stringer

University of North Carolina at Chapel Hill

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Meg Doherty

World Health Organization

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Rachel Baggaley

World Health Organization

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Benjamin H. Chi

University of North Carolina at Chapel Hill

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Thu-Ha Dinh

Centers for Disease Control and Prevention

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