Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, Florida 32610, USA.
AIDS. 2009 Sep 10;23(14):F9-F17. doi: 10.1097/QAD.0b013e32832faf61.
We sought to investigate the evolutionary and historical reasons for the different epidemiological patterns of HIV-1 in the early epidemic. In order to characterize the demographic history of HIV-1 subtypes A and D in east Africa, we examined molecular epidemiology, geographical and historical data.
We employed high-resolution phylodynamics to investigate the introduction of HIV-1A and D into east Africa, the geographic trends of viral spread, and the demographic growth of each subtype. We also used geographic information system data to investigate human migration trends, population growth, and human mobility.
HIV-1A and D were introduced into east Africa after 1950 and spread exponentially during the 1970s, concurrent with eastward expansion. Spatiotemporal data failed to explain the establishment and spread of HIV based on urban population growth and migration. The low prevalence of the virus in the Democratic Republic of Congo before and after the emergence of the pandemic was, however, consistent with regional accessibility data, highlighting the difficulty in travel between major population centers in central Africa. In contrast, the strong interconnectivity between population centers across the east African region since colonial times has likely fostered the rapid growth of the epidemic in this locale.
This study illustrates how phylodynamic analysis of pathogens informed by geospatial data can provide a more holistic and evidence-based interpretation of past epidemics. We advocate that this 'landscape phylodynamics' approach has the potential to provide a framework both to understand epidemics' spread and to design optimal intervention strategies.
我们旨在探讨 HIV-1 在早期流行中不同流行病学模式的进化和历史原因。为了描述东非 HIV-1 亚型 A 和 D 的人口统计学历史，我们检查了分子流行病学、地理和历史数据。
我们采用高分辨率系统发育动力学来研究 HIV-1A 和 D 进入东非的情况、病毒传播的地理趋势以及每个亚型的人口增长情况。我们还使用地理信息系统数据来研究人类迁移趋势、人口增长和人类流动性。
HIV-1A 和 D 于 1950 年后传入东非，并在 20 世纪 70 年代呈指数级传播，与东扩同步。时空数据无法根据城市人口增长和迁移来解释 HIV 的建立和传播。然而，大流行前后刚果民主共和国病毒的低流行率与区域可达性数据一致，突出了中非主要人口中心之间旅行的困难。相比之下，自殖民时代以来，东非地区各人口中心之间的强大互联性可能促进了该地区疫情的快速增长。
本研究说明了病原体的系统发育动力学分析如何通过地理空间数据提供对过去疫情的更全面和基于证据的解释。我们主张，这种“景观系统发育动力学”方法有可能为理解疫情的传播和设计最佳干预策略提供框架。
