Oswaldo Cruz Foundation of Rondônia-FIOCRUZ/RO, Porto Velho RO 76812 245, Rondônia, Brazil.
Research Center in Tropical Medicine of Rondônia -CEPEM/RO, Porto Velho RO 76812 329, Rondônia, Brazil.
Viruses. 2019 Oct 29;11(11):995. doi: 10.3390/v11110995.
The hepatitis delta virus (HDV) is a globally distributed agent, and its genetic variability allows for it to be organized into eight genotypes with different geographic distributions. In South America, genotype 3 (HDV-3) is frequently isolated and responsible for the most severe form of infection. The objective of this study was to evaluate the evolutionary and epidemiological dynamics of HDV-3 over the years and to describe its distribution throughout this continent in an evolutionary perspective. While using Bayesian analysis, with strains being deposited in the Nucleotide database, the most recent common ancestor was dated back to 1964 and phylogenetic analysis indicated that the dispersion may have started in Brazil, spreading to Venezuela and then to Colombia, respectively. Exponential growth in the effective number of infections was observed between the 1950s and 1970s, years after the first report of the presence of HDV on the continent, during the Labrea Black Fever outbreak, which showed that the virus continued to spread, increasing the number of cases decades after the first reports. Subsequently, the analysis showed a decrease in the epidemiological levels of HDV, which was probably due to the implantation of the vaccine against its helper virus, hepatitis B virus, and serological screening methods implemented in the blood banks.
丁型肝炎病毒（HDV）是一种在全球范围内分布的病原体，其遗传变异性使其能够分为具有不同地理分布的 8 个基因型。在南美洲，基因型 3（HDV-3）经常被分离出来，是导致感染最严重的一种。本研究旨在评估 HDV-3 多年来的进化和流行病学动态，并从进化的角度描述其在整个南美洲的分布。通过对保存在核苷酸数据库中的毒株进行贝叶斯分析，最近的共同祖先可以追溯到 1964 年，系统发育分析表明，这种传播可能是从巴西开始的，分别传播到委内瑞拉和哥伦比亚。在 Labrea 黑热病爆发期间，观察到在该大陆首次报告 HDV 存在之后的 50 年代至 70 年代，感染人数的有效增长率呈指数增长，这表明病毒继续传播，在首次报告数十年后，病例数量不断增加。随后，分析显示 HDV 的流行病学水平下降，这可能是由于其辅助病毒乙型肝炎病毒疫苗的接种以及血液库中实施的血清学筛查方法所致。
