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Bacterial and viral infections associated with influenza

Carol Joseph1, Yu Togawa2, Nahoko Shindo3

  • 1Global Influenza Programme, World Health Organization, Geneva, Switzerland.

Influenza and Other Respiratory Viruses
|September 17, 2013
PubMed

Insights

Influenza often leads to severe bacterial and viral co-infections, causing significant illness and death. Understanding these secondary infections is crucial for effective clinical management of influenza patients.

Area of Science:

  • Infectious Diseases
  • Public Health
  • Clinical Medicine

Background:

  • Influenza infections frequently lead to secondary bacterial and viral co-infections, contributing to high morbidity and mortality during seasonal and pandemic outbreaks.
  • These co-infections complicate influenza illness, necessitating a comprehensive understanding of their epidemiology and clinical impact.

Purpose of the Study:

  • To review and evaluate the incidence, epidemiology, etiology, clinical significance, and impact of bacterial and viral co-infections and secondary infections associated with influenza.
  • To provide clinicians with an overview of the spectrum of bacterial and viral infections that can present alongside influenza.

Main Methods:

  • A comprehensive literature review of published articles was conducted.
  • The review covered bacterial and viral infections associated with influenza from 1918 to 2009, including pulmonary and extra-pulmonary infections.
  • Articles published up to December 2011 were included.

Main Results:

  • While Streptococcus pneumoniae is the primary cause of bacterial pneumonia, other bacterial and viral co-infections are significant.
  • Newly identified dual infections associated with the 2009 H1N1 pandemic strain were highlighted.
  • Less common pathogens, such as Legionella pneumophila, can also be associated with influenza, especially with novel strains.

Conclusions:

  • Influenza-associated severe pneumonia is frequently bacterial and requires antibiotic treatment.
  • Clinicians must be aware of the diverse range of bacterial and viral co- or secondary infections that can accompany influenza.
  • Emerging influenza strains may be associated with a broader spectrum of infectious agents.
Keywords:
Co-infectionepidemiologyincidenceinfluenzasecondary infection

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