School of Public Health, University of the Western Cape, Cape Town, South Africa.
Health Section, UNICEF, New York, NY, USA.
BMC Infect Dis. 2019 Sep 16;19(Suppl 1):784. doi: 10.1186/s12879-019-4336-1.
Eliminating mother-to-child transmission of HIV is a global public health target. Robust, feasible methodologies to measure population level impact of programmes to prevent mother-to-child transmission of HIV (PMTCT) are needed in high HIV prevalence settings. We present a summary of the protocol of the South African PMTCT Evaluation (SAPMTCTE) with its revision over three repeated rounds of the survey, 2010-2014.
Three cross sectional surveys (2010, 2011-2012 and 2012-2013) were conducted in 580 primary health care immunisation service points randomly selected after stratified multistage probability proportional to size sampling. All infants aged 4-8 weeks receiving their six-week immunisation at a sampled facility on the day of the visit were eligible to participate. Trained research nurses conducted interviews and took infant dried blood spot (iDBS) samples for HIV enzyme immunoassay (EIA) and total nucleic acid polymerase chain reaction (PCR) testing. Interviews were conducted using mobile phones and iDBS were sent to the National Health Laboratory for testing. All findings were adjusted for study design, non-response, and weighted for number of South African live-birth in each study round. In 2012 a national closed cohort of these 4 to 8-week old infants testing EIA positive (HIV Exposed Infants) from the 2012-2013 cross-sectional survey was established to estimate longer-term PMTCT impact to 18 months. Follow-up analyses were to estimate weighted cumulative MTCT until 18 months, postnatal MTCT from 6 weeks until 18 months and a combined outcome of MTCT-or-death, using a competing risks model, with death as a competing risk. HIV-free survival was defined as a child surviving and HIV-negative up to 18 months or last visit seen. A weighted cumulative incidence analysis was conducted, adjusting for survey design effects.
In the absence of robust high-quality routine medical recording systems, in the context of a generalised HIV epidemic, national surveys can be used to monitor PMTCT effectiveness; however, monitoring long-term outcomes nationally is difficult due to poor retention in care.
消除母婴传播艾滋病毒是全球公共卫生目标。在高艾滋病毒流行地区，需要强有力的、可行的方法来衡量预防母婴传播艾滋病毒（PMTCT）方案对人群的影响。我们介绍了南非 PMTCT 评估（SAPMTCTE）的方案摘要及其在 2010-2014 年期间三次重复调查中的修订。
在 580 个初级卫生保健免疫服务点进行了三次横断面调查（2010 年、2011-2012 年和 2012-2013 年），采用分层多阶段概率比例大小抽样方法随机选择。在访问当天，在抽样设施接受六周龄免疫接种的所有 4-8 周龄婴儿均有资格参加。经过培训的研究护士进行访谈并采集婴儿干血斑（iDBS）样本，用于 HIV 酶免疫分析（EIA）和总核酸聚合酶链反应（PCR）检测。访谈使用移动电话进行，iDBS 被送往国家卫生实验室进行检测。所有发现均根据研究设计、无应答情况进行调整，并根据每个研究轮次南非活产婴儿的数量进行加权。2012 年，从 2012-2013 年的横断面调查中建立了一个全国性的 EIA 阳性（HIV 暴露婴儿）4 至 8 周龄婴儿的闭合队列，以估计更长时间的 PMTCT 影响到 18 个月。随访分析旨在使用竞争风险模型估计加权累积 MTCT 到 18 个月、6 周后到 18 个月的产后 MTCT 和 MTCT 或死亡的综合结局，将死亡作为竞争风险。HIV 无存活定义为存活至 18 个月或最后一次就诊时 HIV 阴性的儿童。进行加权累积发生率分析，调整调查设计效果。
在缺乏强大的高质量常规医疗记录系统的情况下，在普遍存在 HIV 流行的情况下，全国性调查可用于监测 PMTCT 的效果；然而，由于护理保留率差，全国范围内监测长期结果是困难的。
