Pediatr Allergy Respir Dis.  2012 Sep;22(3):292-301.

The Comparison of Clinical Characteristics and Courses of Pediatric Patients Hospitalized with Pandemic Influenza A (H1N1) and Seasonal Influenza from 2009 to 2011

• Yang SI
• Rho JH
• Sun YH
• Cho KH
• Shim SY
• Eun BW
• Kim JE
• Son DW
• Tchah H

Abstract

PURPOSE
Pandemic influenza viruses have caused significant morbidity and mortality. Pandemic influenza A (H1N1) was detected in April 2009 and caused worldwide outbreak. We investigated the differences in clinical characteristics and courses between pandemic and seasonal influenzas.
METHODS
We reviewed the medical records of pediatric patients, (< or =18 years) with influenza hospitalized to Gachon University Gil Medical Center from the 1 April 2009 to the 31 August 2011.
RESULTS
Two hundred twenty-six patients with pandemic influenza and 118 patients with seasonal influenza were included. Age, sex, and proportion of underlying diseases were similar between the two groups. Hypoxemia, shortness of breath, and tachypnea were more common in pandemic influenza.(P<0.05) Oxygen supplementation and radiologically confirmed pneumonia were more common in pandemic influenza.(P<0.005) However, there were no significant differences in the mean duration of hospitalization, proportion of patients admitted to the intensive care unit, need for mechanical ventilation, and death.
CONCLUSION
Pandemic influenza caused more frequently lower respiratory tract infection and pneumonia. However, the courses of pandemic influenza were not different from those of seasonal influenza; probably, due to the effects of several factors, including antiviral therapy.

Keyword

Hospitalization; Influenza; Pandemics; Pediatrics

MeSH Terms

Anoxia
Dyspnea
Hospitalization
Humans
Influenza, Human
Intensive Care Units
Medical Records
Orthomyxoviridae
Oxygen
Pandemics
Pediatrics
Pneumonia
Respiration, Artificial
Respiratory Tract Infections
Seasons
Tachypnea
Oxygen

Figure

• 

  Fig. 1 Epidemiologic curve of date of hospitalization of 2009 pandemic influenza A (H1N1) and seasonal influenza.

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