Clinical and epidemiological characteristics of Human Coronavirus HKU1 and NL63 in children with acute respiratory tract infection during 2009-2011 in Nanjing

Abstract

Objective To investigate the clinical and epidemiological characteristics of Coronavirus HKU1 (Human CoV-HKU1) and NL63 (Human CoV-NL63) in children with acute respiratory tract infection in Nanjing. Methods From August 2009 to July 2011, 1 286 respiratory samples were collected from the outpatient and hospitalized children in the Children′s Hospital of Nanjing Medical University. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect HCoV-HKU1 and NL63 genes, besides, positive samples were used for common respiratory virus screening. The positive amplification products were cloned, sequenced, homologous and phylogenetic analysis was conducted by molecular biological method . Results The detection rate of HCoV-HKU1 was 1.1% (14/1 286), the positive sequences shared a 98.2%-100% nucleotide identity with the HCoV-HKU1 strains and mixed infection rate was 92.9%. The main clinical diagnoses were bronchitis, bronchopneumonia and bronchiolitis. The clinical manifestations were cough, fever, wheezing. The detection rate of HCoV-NL63 was 1.5% (19/1 286), the positive sequences shared a 95.6%-100% nucleotide identity with the HCoV-NL63 strains and mixed infection rate were 63.2%. The main clinical diagnosis were acute upper respiratory tract infection, bronchitis, bronchopneumonia. The clinical manifestations were fever, cough, expectoration. No deaths were found in both HCoV-HKU1 and NL63 infections. Conclusions From August 2009 to July 2011, HCoV-HKU1 and NL63 were detected in children with respiratory tract infection in Nanjing area. HCoV-HKU1 infected cases were lower respiratory tract infection, epidemic in winter and spring, infected cases were mainly under 1 years of age, HCoV-NL63 infected cases including upper respiratory and lower respiratory tract infection, epidemic in the season of summer and autumn. The infected cases were mainly at the age rank from 1 year to 3 years. The clinical manifestations of children infected with coronavirus HKU1 and NL63 are not specificity. Key words: Acute respiratory tract infection; Clinical characteristics; Children; Coronavirus; Epidemiology