Human Rhinoviruses in Korean with Acute Low Respiratory Tract Infections

Human rhinovirus (HRV) must be viewed as a significant etiological agent of acute low respiratory tract infections (ALRIs) in infants and young children. The present study has been carried out to investigate the prevalence of recently identified respiratory viruses and determine the phylogenetic composition of HRV strains. In total, 923 nasopharyngeal aspirates (NPAs) collected from hospitalized patients with ALRIs between January and December 2010 (453 females and 470 males) at five referral hospitals in Seoul were tested for respiratory viruses. Viruses were detected by RT-PCR (Reverse transcription polymerase chain reaction) in 501 (54.3%) of the 923 positive samples obtained. Overall, HRV was detected in 7.9%, ADV in 10.2%, IFV in 21.9%, RSV in 3.6%, hMPV in 2.7%, HCoV in 2.5%, HEV in 1.6%, HBoV in 1.6%, and PIV in 2.4% of the samples. HRV infections occurred throughout the year, with peaks in January, May, July, and November of 2010. Phylogenetic analyses using the VP4/VP2 cording region showed that among the 27 isolates with HRV, 14 (52%) were infected with species A, 2 (7%) were infected with species B, and 11 (41%) were infected with the strains from HRV-C. HRV-C sequences are genetically distinct, sharing only 32% to 33% of their amino acids with HRV-A and HRV-B, while retaining 46% to 100% identity with each other. HRV-A, B, and C were co-circulating in children hospitalized with ALRIs in Korea in 2010. These findings indicated that HRV-C was the important causative agent of HRV associated with ALRIs.