Pediatric Hospitalizations Associated with 2009 Pandemic Influenza A (H1N1) in Argentina

N Engl J of Medicine  January 7, 2010  V.362  N.1  p.45-55

Romina Libster, M.D., Jimena Bugna, M.D., Silvina Coviello, M.S., Diego R. Hijano, M.D., Mariana Dunaiewsky, M.D., Natalia Reynoso, M.D., Maria L. Cavalieri, M.D., Maria C. Guglielmo, M.D., M. Soledad Areso, M.D., Tomas Gilligan, M.D., Fernanda Santucho, M.D., Graciela Cabral, M.D., Gabriela L. Gregorio, M.D., Rina Moreno, M.D., Maria I. Lutz, M.D., Alicia L. Panigasi, M.D., Liliana Saligari, M.D., Mauricio T. Caballero, M.D., Rodrigo M. Egües Almeida, M.D., Maria E. Gutierrez Meyer, M.D., Maria D. Neder, M.D., Maria C. Davenport, M.D., Maria P. Del Valle, M.D., Valeria S. Santidrian, M.D., Guillermina Mosca, M.D., Mercedes Garcia Domínguez, M.D., Liliana Alvarez, M.D., Patricia Landa, M.D., Ana Pota, M.D., Norma Boloñati, M.D., Ricardo Dalamon, M.D., Victoria I. Sanchez Mercol, M.D., Marco Espinoza, M.D., Juan Carlos Peuchot, M.D., Ariel Karolinski, M.D., Miriam Bruno, M.D., Ana Borsa, M.D., Fernando Ferrero, M.D., Ph.D., Angel Bonina, M.D., Margarita Ramonet, M.D., Lidia C. Albano, M.D., Nora Luedicke, M.D., Elias Alterman, M.D., Vilma Savy, Ph.D., Elsa Baumeister, Ph.D., James D. Chappell, M.D., Ph.D., Kathryn M. Edwards, M.D., Guillermina A. Melendi, M.D., and Fernando P. Polack, M.D.

Background

While the Northern Hemisphere experiences the effects of the 2009 pandemic influenza A (H1N1) virus, data from the recent influenza season in the Southern Hemisphere can provide important information on the burden of disease in children.

Methods

We conducted a retrospective case series involving children with acute infection of the lower respiratory tract or fever in whom 2009 H1N1 influenza was diagnosed on reverse-transcriptase polymerase-chain-reaction assay and who were admitted to one of six pediatric hospitals serving a catchment area of 1.2 million children. We compared rates of admission and death with those among age-matched children who had been infected with seasonal influenza strains in previous years.

Results

Between May and July 2009, a total of 251 children were hospitalized with 2009 H1N1 influenza. Rates of hospitalization were double those for seasonal influenza in 2008. Of the children who were hospitalized, 47 (19%) were admitted to an intensive care unit, 42 (17%) required mechanical ventilation, and 13 (5%) died. The overall rate of death was 1.1 per 100,000 children, as compared with 0.1 per 100,000 children for seasonal influenza in 2007. (No pediatric deaths associated with seasonal influenza were reported in 2008.) Most deaths were caused by refractory hypoxemia in infants under 1 year of age (death rate, 7.6 per 100,000).

Conclusions

Pandemic 2009 H1N1 influenza was associated with pediatric death rates that were 10 times the rates for seasonal influenza in previous years.

abstract

http://content.nejm.org/cgi/content/full/362/1/45?query=TOC

PDF

http://content.nejm.org/cgi/reprint/362/1/45.pdf