Abstract
Objective
To describe the clinical characteristics and outcome of Indian children infected with 2009 H1N1 influenza virus.
Study design
Retrospective chart review.
Setting
Outpatient department and hospitalized patients in a tertiary care hospital.
Methods
Clinical details of 85 children (positive for the 2009 H1N1 virus infection tested by real-time reverse-transcriptase-polymerase-chain-reaction assay) were analyzed from medical charts.
Results
Of the 85 (55 boys) children positive for 2009 H1N1 virus infection, 64.7% were between 5 years to 16 years, and 35.3% were below 5 years age. The mean age of these children was 7.5±3.5 yr. Contact history was positive only in 22 (26%) cases. High grade fever was the most common symptom, followed by cough and rhinorrhea. Twenty-nine (34%) patients had an underlying co-morbid condition. Of the 34 patients who underwent chest radiography during evaluation, 18 children (52.9%) had findings consistent with lower respiratory tract infection. Antiviral therapy was initiated in 76 patients. Hospitalization was required in 30 (35.3%) children. Risk factors for hospitalization included underlying co-morbid condition, respiratory distress, vomiting, wheezing, diarrhea, hypotension and infiltrates/consolidation on chest radiograph. Mean length of hospitalization was 131±76 hours, irrespective of underlying disease. Three children developed Acute Respiratory Distress Syndrome and died.
Conclusions
Clinical features and routine laboratory investigations in children with swine origin influenza were non-specific. Children with co-morbid condition, respiratory distress, vomiting, wheezing, diarrhea, hypotension and infiltrates/consolidation on chest radiograph were at higher risk of hospitalization.
Key words: Acute lung injury, ARDS, H1N1 influenza, Pandemic influenza, Swine origin influenza
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