Host genome depletion to determine the evolution, genetic diversity and transmission patterns of full genome sequences of African swine fever genotype IX from Uganda

Abstract

African swine fever (ASF) is a highly contagious viral haemorrhagic disease of domestic pigs, wild boar and feral swine. It is caused by the only DNA arbovirus, African swine fever virus (ASFV), which is the only member of the family Asfarviridae and is transmitted by the soft ticks in the genus Ornithodoros. ASF results in mortalities of up to 100% and exhibits different epidemiological patterns in Africa, Europe and Asia. This ASFV has recently spread to other countries in Europe and is also now present in Asia where it has spread like wildfire, resulting into high economic losses. The lack of a treatment or vaccine against this disease makes its control and prevention extremely difficult. This is partly due to the large size of the ASFV genome (170-190 kbp) and the many genes (187–190) that it encodes. There are currently 24 genotypes, with genotype IX predominating in Uganda and Kenya. Understanding the genetic characteristics of ASFV have focused mainly on partial fragments of selected genes, thus missing the opportunity to investigate the evolution, genetic diversity and patterns of transmission at the whole genomic level. Using the host-genome depletion approach we show an increase in the amount of ASFV DNA recovered directly from clinical material and generate genotype IX complete genomes on an NGS platform. We further show the inter-epidemic relationships of ASFV outbreaks in Uganda. The data contribute towards understanding the patterns and dynamics of transmission and maintenance of ASFV in a country in which ASF is endemic.

African Swine Fever Virus Circulation between Tanzania and Neighboring Countries: A Systematic Review and Meta-Analysis

“…The ASFV p72 genotype IX was recovered from domestic pigs and warthogs. This genotype is described as the most predominant in Uganda and Kenya [ 42 ], but also, it was described in DRC [ 50 , 53 ] and Tanzania [ 56 , 62 ]. Although associated with lethal ASF outbreaks [ 21 , 47 , 48 ], an increasing number of studies reported the genotype IX in asymptomatic domestic pigs in Tanzania [ 56 ], DRC [ 50 ], Uganda [ 44 ], and Kenya [ 65 ].…”

“…Zambia recorded a wider variety of ASFV p72 genotypes with seven genotypes being reported to circulate in the country, namely genotypes I, II, VIII, XI, XII, XIII, and XIV. [40] p72, p54, p30, CVR II Domestic pig [41] p72, p54 I Domestic pig [22] p72 I, II, VIII, XI, XII, XIII, XIV Domestic pig and tick [23] p72, CVR I, VIII Tick and domestic pig [17] p72, p54, CVR I, II, XIV Domestic pig [42] WGS IX Domestic pig Uganda (10) [43] p72, p54, CVR IX Domestic pig [44] p72, p54, CVR IX Domestic pig [45] p72, p54, CVR IX Domestic pig [46] WGS IX Domestic pig [47] p72, p54, CVR IX Domestic pig [21] p72, p54, CVR IX, X Domestic pig [22] p72 IX Domestic pig [23] p72, CVR IX, X Domestic pig [48] p72, p54, CVR, TK IX Domestic pig [49] p72, CVR II, V, VI, VIII Domestic pig…”