The clinical features, risk of prolonged hospitalization and household infections of hospitalized children for pandemic 2009 influenza A (H1N1) virus infection in Thailand.
Udompornwattana S., Srajai K., Suwan P., Tangsathapornpong A., Wittawatmongkol O., Phongsamart W., Vanprapar N., Nuntarukchaikul M., Taeprasert P., Sricharoenchai S., Tanchaweng S., Phutwattana P., Taylor WRJ., Maleesatharn A., Chokephaibulkit K.
OBJECTIVE: To evaluate the clinical features, risk of prolonged hospitalization, and household infection in Thai children hospitalized with 2009 pandemic influenza A/H1N1 virus (pH1N1). MATERIAL AND METHOD: The authors conducted a retrospective chart review of children hospitalized in four Thai tertiary care hospitals between June 1 and September 30, 2009, with reverse-transcriptase-polymerase-chain-reaction confirmed pH1N1. Household contact data were obtained by telephone. RESULTS: Pediatric admissions numbered 115, 58 were females (50.4%). Median age was 5.2 (range 0.5 to 15) years. Fifty-one (44.4%) children had underlying diseases, most commonly asthma 17 (14.8%). Median preadmission illness duration was two days (range 1 to 10). Sixty-one (53.0%) children had lymphopenia. Chest X-ray infiltration was detected in 89 (77.4%) children. Oseltamivir was prescribed in 104 (90.4%) children; 47(45.2%) within 48 hours of illness. 70 (60.9%) children received antibiotics. The median hospitalization was three days (range 1 to 94). Independent (multivariate analysis) factors associated with prolonged hospitalization (> or = 7 days) were aged five to nine years (OR 7.4; 95% CI 1.1-48.9, p = 0.037) and having an underlying disease (OR 5.9; 95% CI 1.5-23.3, p = 0.01). Five (4.3%) children required mechanical ventilation; two (1.7%) children died. Household data showed that 63 of 109 (57.8%) patients had contact with a suspected or confirmed pH1N1 case. There were 39 (15.7%) of 249 household contacts who were probable secondary cases: 23 suspected and 16 confirmed pH1N1 of whom 25 (64.1%) were aged < or = 18 years. CONCLUSION: Most pH1N1 infected hospitalized children had pneumonia, an uneventful short hospitalization, and a low in hospital mortality. Half of the patients were household acquired. Secondary household cases affected mostly children.