OBJECTIVESince late March 2009, a novel influenza H1N1 strain emerged in humans in Mexico and the United States. It has rapidly spread to many countries on different continents, prompting unprecedented activation of pandemic preparedness plans. The present study aimed to investigate the characteristics of children with the novel influenza A (H1N1) virus infection.

METHODTwelve cases with influenza A (H1N1) infection were diagnosed according to the criteria of the Center for Disease Control and Prevention (CDC) of China during 1 May to 15 July 2009 in the Pediatric Hospital of Fudan University were analyzed. Influenza A (H1N1) RNA was detected by RT-PCR in CDC Shanghai China.

RESULTAll the 12 children with the novel influenza A (H1N1) virus infection were imported cases, aged from 11 months to 14 years 7 months, 7 of whom were boys, 5 were girls. Five cases contacted closely with influenza A (H1N1) patients; 12 cases had fever and no vomiting or diarrhea; 7 had cough or runny nose or anorexia. One had shortness of breath. Of the 11 cases who could tell about symptoms correctly, 6 had sore throat, 3 had stomachache, and none had muscle pain. Two of the 12 cases had pneumonia, and the disease in 1 of them was fatal and needed intensive care. One case was isolated and treated at home. The 11 cases hospitalized were treated according to the guidance of influenza A (H1N1) diagnosis and treatment issued by the Ministry of Health of China. Ten hospitalized cases were treated with oseltamivir. All the cases recovered completely. The median length of hospital stay was 8.1 days (range, 6 to 16), and the time of negative test results of influenza A (H1N1) RNA from illness onset to collection of samples for viral testing was from 5 to 15 days.

CONCLUSIONSymptoms among children with the novel influenza A (H1N1) virus infection were classic and the majority of the cases we treated had a mild clinical course if they were isolated and treated promptly. Antivirals appears to have not had any major adverse effects. More data from different regions and large samples are needed to illuminate the characteristics of children with novel influenza A (H1N1) virus infection.