Clinical manifestations of human coronavirus NL63 infection in children in Taiwan

Abstract

Human coronavirus NL63 (HCoV-NL63) is a global respiratory tract pathogen; however, the epidemiology of this virus in subtropical area is not well known. To evaluate the epidemics and disease spectrum of HCoV-NL63 infection in children in Taiwan, we prospectively screened children admitted to the hospital with respiratory tract infection from May 2004 to April 2005. Every enrolled child had a nasopharyngeal aspirate (NPA) sample taken. Quantitative RT-PCR was used to detect 1b gene of HCoV-NL63. A total of 539 NPAs were collected. Seven (1.3%) were positive for HCoV-NL63. All cases were boys younger than 3 years of age and most cases occurred in autumn. Co-infection with other pathogens was observed in three cases. The most common symptoms/signs of HCoV-NL63 infection were cough, fever, and inspiratory stridor. HCoV-NL63 was the most common pathogen (14.7%) in children with croup and was the cause of three cases of croup in October. The odds ratio of croup in children infected with HCoV-NL63 was 43.4 (95% CI 8.1 approximately 233.1). In conclusion, HCoV-NL63 is an important respiratory tract pathogen as the main cause in children admitted to the hospital in Taiwan.

Fig. 1

Positive real time RT-PCR rate of HCoV-NL63 from May 2004 to April 2005

Fig. 2

Phylogenetic analysis of partial spike gene region (654 bp) of HCoV-NL63. Phylogenetic trees were constructed by the neighbor-joining method, and bootstrap values were determined by 1,000 replicates in DNAMAN, version 5.2.2. Two available sequences in Taiwan (nos. 567 and 754) and other reference sequences obtained in GenBank (DQ445911, DQ445912, AY518894, AY567487) were included. HCoV-229E (DQ243986) is used as an outgroup. Genetic sequences from five other NPA specimens could not be obtained due to lower PCR product amplification

Fig. 3

The incidence of croup and viral epidemics in NTUH from May 2004 to April 2005