ZVITAMBO Project, Harare, Zimbabwe.
Int J Epidemiol. 2011 Aug;40(4):945-54. doi: 10.1093/ije/dyr055. Epub 2011 Apr 5.
The BED assay was developed to estimate the proportion of recent HIV infections in a population. We used the BED assay as a proxy for acute infection to quantify the associated risk of mother-to-child-transmission (MTCT) during pregnancy and delivery. Design A total of 3773 HIV-1 sero-positive women were tested within 96 h of delivery using the BED assay, and CD4 cell count measurements were taken. Mothers were classified according to their likelihood of having recently seroconverted.
The risk of MTCT in utero and intra-partum was assessed comparing different groups defined by BED and CD4 cell count, adjusting for background factors using multinomial logistic models.
Compared with women with BED ≥ 0.8/CD4 ≥ 350 (typical of HIV-1 chronic patients) there was insufficient evidence to conclude that women presenting with BED < 0.8/CD4 ≥ 350 (typical of recent infections) were more likely to transmit in utero [adjusted odds ratio (aOR) = 1.37, 96% confidence interval (CI) 0.90-2.08, P = 0.14], whereas women with BED < 0.8/CD4 200-349 (possibly recently infected patients) had a 2.57 (95% CI 1.39-4.77, P-value < 0.01) odds of transmitting in utero. Women who had BED < 0.8/CD4 < 200 were most likely to transmit in utero (aOR 3.73, 95% CI 1.27-10.96, P = 0.02). BED and CD4 cell count were not predictive of intra-partum infections.
These data provide evidence that in utero transmission of HIV might be higher among women who seroconvert during pregnancy.
BED 检测法旨在估计人群中近期 HIV 感染的比例。我们使用 BED 检测法作为急性感染的替代指标，定量评估怀孕期间和分娩时母婴传播（MTCT）的相关风险。
共有 3773 名 HIV-1 血清阳性妇女在分娩后 96 小时内使用 BED 检测法进行检测，并进行 CD4 细胞计数测量。根据近期血清转换的可能性对母亲进行分类。
使用多项逻辑回归模型，通过 BED 和 CD4 细胞计数将不同组别的 MTCT 风险进行调整，比较不同组别的风险，调整背景因素。
与 BED≥0.8/CD4≥350（HIV-1 慢性患者的典型特征）的妇女相比，BED<0.8/CD4≥350（近期感染的典型特征）的妇女发生宫内传播的证据不足[调整后的比值比（aOR）=1.37，96%置信区间（CI）0.90-2.08，P=0.14]，而 BED<0.8/CD4 200-349（可能近期感染的患者）的妇女宫内传播的可能性高 2.57 倍（95%CI 1.39-4.77，P 值<0.01）。BED<0.8/CD4<200 的妇女最有可能发生宫内传播（aOR 3.73，95%CI 1.27-10.96，P=0.02）。BED 和 CD4 细胞计数不能预测分娩期间的感染。
这些数据表明，在怀孕期间发生血清转换的妇女中，HIV 的宫内传播可能更高。
