2009 H1N1 influenza A in children: a descriptive clinical study

BACKGROUND AND OBJECTIVE: The 2009 H1N1 was a new influenza virus causing illness in people. Especially those younger than 5 years of age and those who have high-risk medical conditions are at increased risk for influenza-related complications. In the present study, we describe the clinical presentation of the H1N1 cases attending Jeddah Clinic Hospital-Al Kandarah (JCH-K) in the time period from October 2009 to January 2010, and identified the high-risk age groups. DESIGN AND SETTING: Prospective study at JCH-K from October 2009 through January 2010. PATIENTS AND METHODS: All pediatric patients (up to 15 years old) presenting with influenza-like illnesses in the clinics during the specified period were clinically examined and tested using reverse transcriptase polymerase chain reaction. Only confirmed H1N1 cases were included in the study. RESULTS: Over a 4-month period, 89 cases of laboratory-confirmed H1N1 were reported in JCH-K. Thirty-four patients (38.2%) were younger than 5 years of age. Forty-six (51.6%) cases were males. Thirty-three cases were Saudis (37.1%). The most commonly reported symptom was fever, which was noted in all cases. Twenty-eight cases (31.5%) had pneumonia. Fourteen cases (15.7%) were known asthmatics. Fifty-two (58.4%) cases were lymphopenic and 32 (35.9%) cases were leucopenic. Sixty-five (73%) patients were hospitalized, and five of them were treated in the intensive care unit. CONCLUSIONS: Even though the majority of cases of the 2009 pandemic influenza A H1N1 were mild, a severe disease does occur in children. In view of delayed PCR results, clinical presentation and lymphopenia were used as diagnostic criteria to start antiviral treatment as early as possible. No deaths were attributed to the 2009 pandemic.