Genomic Features and Evolution of the Parapoxvirus during the Past Two Decades

Abstract

Parapoxvirus (PPV) has been identified in some mammals and poses a great threat to both the livestock production and public health. However, the prevalence and evolution of this virus are still not fully understood. Here, we performed an in silico analysis to investigate the genomic features and evolution of PPVs. We noticed that although there were significant differences of GC contents between orf virus (ORFV) and other three species of PPVs, all PPVs showed almost identical nucleotide bias, that is GC richness. The structural analysis of PPV genomes showed the divergence of different PPV species, which may be due to the specific adaptation to their natural hosts. Additionally, we estimated the phylogenetic diversity of seven different genes of PPV. According to all available sequences, our results suggested that during 2010–2018, ORFV was the dominant virus species under the selective pressure of the optimal gene patterns. Furthermore, we found the substitution rates ranged from 3.56 × 10−5 to 4.21 × 10−4 in different PPV segments, and the PPV VIR gene evolved at the highest substitution rate. In these seven protein-coding regions, purifying selection was the major evolutionary pressure, while the GIF and VIR genes suffered the greatest positive selection pressure. These results may provide useful knowledge on the virus genetic evolution from a new perspective which could help to create prevention and control strategies.

Equine dermatitis outbreak associated with parapoxvirus

“…Sequences from 2021 to 2022 indicated that the virus had barely mutated. This suggests a common source of infection and is no surprise as the evolutionary rate of large DNA viruses is slow [35] and previous studies have reported mutation rates of 10 −6 –10 −4 substitutions/site/year for poxviruses [36, 37]. Even though analysing the viral sequences can be used to track outbreaks and estimate transmission routes of many viruses, partial Sanger sequencing of the circulating EqPPV variants could not be applied for this outbreak due to nonexisting variation.…”

Pockenvirusinfektionen in der Dermatologie

“…Virokine sind virale Homologe ihrer oft antiinflammatorischen Pendants im Wirt, zum Beispiel virales IL-10 von Parapoxviren. 22 Natürliche Killerzellen, CD4 + und CD8 + Lymphozyten spielen als Teil des adaptiven Immunsystems eine Schlüsselrolle bei der Virusbeseitigung zur Kontrolle der Primärinfektion. 23,24 Pockenvirusinfektionen können die Lebensqualität stark beeinträchtigen, insbesondere bei komplizierten Erkrankungsverläufen mit Beteiligung des zentralen Nervensystems (ZNS), der Atemwege oder des Binde-und Stützgewebes, die auf peri-/postinfektiöse Prozesse, aber auch auf die direkte Virusinfektion zurückzuführen sind.…”

Poxvirus infections in dermatology – the neglected, the notable, and the notorious

“…viral IL-10 of parapoxviruses which can suppress immune response. 22 Natural killer cells, CD4 + and CD8 + lymphocytes, as part of the adaptive immune system, play a key role in viral clearance to control primary infection. 23,24 Only limited data is available on the risk of reinfection with a certain poxvirus species or strain, leading to symptomatic disease again.…”