Setting: Two Pediatric Clinics at the University of Study of Milan, in Milan, Italy (‘L. Sacco’ and ‘S. Paolo’ Hospitals); Department of Public Health-Microbiology-Virology, University of Milan.
Epidemiological and clinical features of respiratory viral infections in hospitalized children during the circulation of influenza virus A(H1N1) 2009
Article first published online: 25 MAY 2011
© 2011 Blackwell Publishing Ltd
Influenza and Other Respiratory Viruses
Volume 5, Issue 6, pages e528–e534, November 2011
How to Cite
Zuccotti, G., Dilillo, D., Zappa, A., Galli, E., Amendola, A., Martinelli, M., Pariani, E., Salvini, F., Tanzi, E., Riva, E. and Giovannini, M. (2011), Epidemiological and clinical features of respiratory viral infections in hospitalized children during the circulation of influenza virus A(H1N1) 2009. Influenza and Other Respiratory Viruses, 5: e528–e534. doi: 10.1111/j.1750-2659.2011.00264.x
- Issue published online: 18 OCT 2011
- Article first published online: 25 MAY 2011
- Accepted 27 April 2011. Published Online 25 May 2011.
- Acute respiratory tract infections;
- emerging viruses;
- influenza virus A(H1N1) 2009;
- pediatric hospitalizations;
- viral respiratory infections
Please cite this paper as: Zuccotti et al. (2011) Epidemiological and clinical features of respiratory viral infections in hospitalized children during the circulation of influenza virus A(H1N1) 2009. Influenza and Other Respiratory Viruses 5(6), e528–e534.
Background Seasonal influenza viruses and respiratory syncytial virus (RSV) are primary causes of acute respiratory tract infections (ARTIs) in children. New respiratory viruses including human metapneumovirus (hMPV), human bocavirus (hBoV), and influenza 2009 A(H1N1) virus have a strong impact on the pediatric population.
Objectives To evaluate epidemiological and clinical features of ARTIs in hospitalized children.
Methods From December 1, 2008, to December 31, 2009, all children under age fifteen (n = 575) hospitalized for ARTIs were investigated for influenza A (subtype H1N1, H3N2, and 2009 H1N1) and B, RSV A and B, hMPV, and hBoV by PCR.
Results Fifty-one percent of samples were positive for these respiratory viruses. The frequencies of virus detection were RSV 34·1%, hBoV 6·8%, hMPV 5%, seasonal influenza A 5%, and seasonal influenza B 0%. From April 2009, 11·6% of collected samples were influenza 2009 A(H1N1) positive. Respiratory syncytial virus activity peaked in January, hBoV in February, and hMPV in April. Seasonal influenza A was detected only between January and April 2009, while influenza 2009 A(H1N1) peaked in November. Respiratory syncytial virus and hMPV were mainly associated with lower respiratory tract infections (LRTIs) and with necessity of O2 administration. The 2009 pandemic influenza was more frequently detected in elder children (P < 0·001) and was associated with higher, longer-lasting fevers compared with other viral infections (P < 0·05).
Conclusions All considered viruses were involved in LRTIs. The primary clinical relevance of RSV and a similar involvement of both seasonal influenza and emerging viruses investigated were observed on the pediatric population.