Summary
Objectives
After the last pandemic the knowledge regarding influenza A infection has improved
however, the outcomes of influenza B infection remain poorly studied. The aim of this
study was to compare the features of influenza B versus influenza A(H1N1)pdm09 infections
during the 2010–2011 epidemic-season.
Methods
A prospective, observational-cohort of adults with laboratory-confirmed influenza
infection during the 2010–2011 epidemic-season was studied
Results
Fifty cases of influenza B and 80 of influenza A(H1N1)pdm09 infection were enrolled.
Among patients with influenza B, the median age was 34 years-old (23–64), 30% pregnant,
24% obese, 34% transplant recipients and 14% with bacterial co-infection. Twenty-eight
percent of patients had pneumonia with alveolar localized pattern and five (10%) died.
Pneumonia was associated with delayed antiviral therapy, older age, higher Charlson
score, invasive mechanical ventilation and bacterial co-infection. Obesity and pregnancy
were not associated with complicated influenza B infection. The proportion of pneumonia,
admission to the ICU and mortality did not differ between cases of influenza A(H1N1)pdm09
and influenza B infection.
Conclusions
Influenza B infection causes severe infection and it is associated with pneumonia
or death, similar to influenza A(H1N1)pdm09 infection. Rapid diagnosis and early antiviral
therapy are necessary for managing influenza pneumonia during epidemic periods.
Keywords
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Article info
Publication history
Published online: July 23, 2012
Accepted:
July 14,
2012
Identification
Copyright
© 2012 The British Infection Association. Published by Elsevier Inc. All rights reserved.
