Pediatr Allergy Respir Dis.  2011 Dec;21(4):269-276.

Comparisons of Clinical Features among Influenza A (H1N1) and Seasonal Influenza A and B during 2009 to 2010 at a Single Institution

• Kang TG
• Kim MJ
• Kim BG
• An HS
• Yun HJ
• Choi EJ
• Jung JA

Abstract

PURPOSE
This study was performed to compare the clinical features of pediatric patients who were diagnosed with influenza A (H1N1) or seasonal influenza A and B during 2009 and 2010 at a single institution.
METHODS
Among children who visited the Dong-A University Hospital with fever (>37.8degrees C) and acute respiratory symptoms from September 2009 to February 2010, 1,004 children who were diagnosed with influenza A (H1N1) or seasonal influenza A and B by reverse transcription-polymerase chain reaction (RT-PCR) were enrolled. Monthly incidence, fever duration before diagnosis, symptoms (fever, cough, rhinorrhea, sore throat, headache, vomiting, abdominal pain, diarrhea, seizure, and dyspnea) and signs (rales, wheezing) were reviewed retrospectively in each group based on medical records.
RESULTS
Influenza A (H1N1) was detected in 944 patients (94.0%), followed by seasonal influenza A in 42 (4.2%) and seasonal influenza B in 8 (1.8%). The positive rate of influenza infection was highest in November 2009 (n=557, 55.5%). Mean duration of fever before RT-PCR was 1.6 days (range, 1.5 to 1.8 days). Except fever, cough was the most common symptom (n=792, 78.9%), followed by rhinorrhea in 407 patients (40.5%). Rales and wheezing were detected in 16 patients (1.6%) and 19 (1.9%), respectively. Significant differences were observed for the number of patients who had cough, headache, vomiting, and wheezing among the three groups (P<0.05).
CONCLUSION
Although the incidence of cough, headache, vomiting, and wheezing differed significantly among the three groups, the number of patients in each group was too different to compare the results.

Keyword

Influenza A (H1N1); Seasonal Influenza A; Seasonal Influenza B

MeSH Terms

Abdominal Pain
Child
Cough
Diarrhea
Fever
Headache
Humans
Incidence
Influenza, Human
Pharyngitis
Respiratory Sounds
Retrospective Studies
Seasons
Seizures
Vomiting

Reference

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