Experimental Medicine, University of Rome "Tor Vergata", Rome, Italy
Oncology and Oncohematology, University of Milan, Milan, Italy.
Sex Transm Infect. 2019 Dec;95(8):619-625. doi: 10.1136/sextrans-2019-054017. Epub 2019 May 10.
We evaluated the characteristics of HIV-1 molecular transmission clusters (MTCs) in 1890 newly diagnosed individuals infected with non-B subtypes between 2005 and 2017 in Italy.
Phylogenetic analyses were performed on sequences to characterise subtypes/circulating recombinant forms and identify MTCs. MTCs were divided into small (SMTCs, 2-3 sequences), medium (MMTCs, 4-9 sequences) and large (LMTCs, ≥10 sequences). Factors associated with MTCs were evaluated using logistic regression analysis.
145 MTCs were identified and involved 666 individuals (35.2%); 319 of them (16.9%) were included in 13 LMTCs, 111 (5.9%) in 20 MMTCs and 236 (12.5%) in 112 SMTCs. Compared with individuals out of MTCs, individuals involved in MTCs were prevalently Italian (72.7% vs 30.9%, p<0.001), male (82.9% vs 62.3%, p<0.001) and men who have sex with men (MSM) (43.5% vs 14.5%, p<0.001). Individuals in MTCs were also younger (median (IQR) years: 41 (35-49) vs 43 (36-51), p<0.001) and had higher CD4 cell count in comparison with individuals out of MTCs (median (IQR): 10/L: 0.4 (0.265-0.587) vs 0.246 (0.082-0.417), p<0.001). The viral load remained stable between the two groups (median (IQR) log copies/mL: 4.8 (4.2-5.5) vs 5.0 (4.3-5.5), p=0.87). Logistic regression confirmed that certain factors such as being MSM, of Italian origin, younger age and higher CD4 cell count were significantly associated with MTCs.
Our findings show that HIV-1 newly diagnosed individuals infected with non-B subtypes are involved in several MTCs in Italy. These MTCs include mainly Italians and MSM and highlight the complex phenomenon characterising the HIV-1 spread. This is important especially in view of monitoring the HIV epidemic and guiding the public health response.
我们评估了 2005 年至 2017 年间意大利 1890 名新诊断为非 B 亚型 HIV-1 感染者中 HIV-1 分子传播簇（MTC）的特征。
对序列进行系统发育分析，以确定亚型/循环重组形式，并识别 MTC。MTC 分为小（SMTC，2-3 个序列）、中（MMTC，4-9 个序列）和大（LMTC，≥10 个序列）。使用逻辑回归分析评估与 MTC 相关的因素。
鉴定出 145 个 MTC，涉及 666 人（35.2%）；其中 319 人（16.9%）包含在 13 个 LMTC 中，111 人（5.9%）包含在 20 个 MMTC 中，236 人（12.5%）包含在 112 个 SMTC 中。与非 MTC 个体相比，MTC 个体更常见于意大利人（72.7%比 30.9%，p<0.001）、男性（82.9%比 62.3%，p<0.001）和男男性行为者（MSM）（43.5%比 14.5%，p<0.001）。MTC 中的个体也更年轻（中位数（IQR）岁：41（35-49）比 43（36-51），p<0.001），且 CD4 细胞计数高于非 MTC 个体（中位数（IQR）：0.4（0.265-0.587）比 0.246（0.082-0.417），p<0.001）。两组间病毒载量保持稳定（中位数（IQR）log 拷贝/ml：4.8（4.2-5.5）比 5.0（4.3-5.5），p=0.87）。逻辑回归证实，某些因素如 MSM、意大利裔、年龄较小和较高的 CD4 细胞计数与 MTC 显著相关。
我们的发现表明，感染非 B 亚型的新诊断 HIV-1 个体参与了意大利的多个 MTC。这些 MTC 主要包括意大利人和 MSM，并突出了 HIV-1 传播特征的复杂现象。这一点很重要，尤其是在监测 HIV 流行和指导公共卫生应对方面。
