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Modulation of potential respiratory pathogens by pH1N1 viral infection

R K-K Leung1, J-W Zhou, W Guan

  • 1Hong Kong Bioinformatics Centre, The Chinese University of Hong Kong, Hong Kong, China.

Clinical Microbiology and Infection : the Official Publication of the European Society of Clinical Microbiology and Infectious Diseases
|November 22, 2012
PubMed

Insights

Influenza A pdm09 virus (pH1N1) infection alters the oropharyngeal microbiota, promoting the growth of potential pathogens like Pseudomonas species. These bacteria possess genes for motility, aiding their access to weakened respiratory tracts, leading to secondary infections.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Genomics

Background:

  • The influenza A pandemic strain H1N1 (pH1N1) caused a global pandemic, but its impact on secondary bacterial infections remains understudied.
  • Understanding the oropharyngeal microbiota's role in pH1N1-associated secondary infections is crucial for effective treatment.

Purpose of the Study:

  • To characterize the oropharyngeal microbiota composition in patients with and without pH1N1 infection.
  • To identify bacterial species and genetic factors associated with secondary infections in pH1N1 patients.

Main Methods:

  • Unbiased high-throughput sequencing was used to analyze oropharyngeal microbiota from pneumonia patients.
  • Comparison of bacterial populations and their genetic profiles between pH1N1-infected and non-infected groups.

Main Results:

  • Pseudomonas species, possessing chemotaxis and flagellar assembly genes, significantly increased (>20-fold) in pH1N1-infected patients.
  • Bacillus and Ralstonia species also increased significantly (5-10-fold) and had similar signaling and motility genes.
  • Common pathogens (Acinetobacter, Streptococcus pneumoniae) and oral commensals (Prevotella, Veillonella, Neisseria) showed no significant increase or decreased in pH1N1 patients.

Conclusions:

  • pH1N1 infection creates a favorable environment for specific bacterial pathogens with enhanced motility.
  • These opportunistic pathogens may exploit weakened immunity to cause secondary respiratory infections.
  • The study highlights a shift in the oropharyngeal microbiome during pH1N1 infection, favoring potential pathogens.
Keywords:
Cell motilitychemotaxismicrobiotapH1N1pneumonia

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