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Updated: Jun 26, 2026

Generation of Recombinant Influenza Virus from Plasmid DNA
11:31

Generation of Recombinant Influenza Virus from Plasmid DNA

Published on: August 3, 2010

The matrix segment of the "Spanish flu" virus originated from intragenic recombination between avian and human

Cheng-Qiang He1, Mei He1, Hong-Bin He1

  • 1The Key Laboratory of Animal Resistant Biology of Shandong, College of Life Science, Shandong Normal University, Jinan, China.

Transboundary and Emerging Diseases
|June 27, 2019
PubMed

Insights

The 1918 Spanish flu

Area of Science:

  • Virology
  • Genetics
  • Epidemiology

Background:

  • The 1918 Spanish flu pandemic caused over 50 million deaths globally.
  • The precise mechanisms behind its high pathogenicity and the virus's origins remain subjects of debate.

Purpose of the Study:

  • To investigate the genetic origins and evolutionary mechanisms contributing to the high pathogenicity of the 1918 Spanish flu virus.
  • To elucidate the role of genetic recombination and reassortment in the emergence of this deadly influenza strain.

Main Methods:

  • Phylogenetic analysis of viral gene segments, specifically focusing on the matrix (M) segment.
  • Comparative genomic analysis to identify origins of other segments like neuraminidase (NA) and non-structural (NS).

Main Results:

  • The matrix (M) segment of the 1918 Spanish flu virus is a recombinant chimera, with origins in avian and human influenza viruses.
  • This unique M segment likely enhanced viral replication capacity, contributing to its high pathogenicity.
  • Phylogenetic evidence confirmed an avian origin for the virus, with reassortment involving avian and mammalian viruses for NA and NS segments.

Conclusions:

  • Genetic recombination, particularly within the M segment, played a crucial role in the high pathogenicity of the 1918 Spanish flu.
  • The findings provide direct phylogenetic evidence supporting an avian origin for the 1918 pandemic influenza A virus.

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