High prevalence of human rhinovirus C infection in Thai children with acute lower respiratory tract disease.
OBJECTIVE
To determine the prevalence of human rhinoviruses (HRV) infections in children with lower respiratory disease in Thailand and monitor the association between species of HRV and clinical presentation in hospitalized paediatric patients.


METHODS
Two hundred and eighty-nine nasopharyngeal (NP) suction specimens were collected from hospitalized paediatric patients admitted to King Chulalongkorn Memorial Hospital, Thailand during February 2006-2007. Nucleic acids were extracted from each sample with subsequent amplification of VP4/2 by semi-nested RT-PCR for HRV detection. Other viral respiratory pathogens were also detected by PCR, RT-PCR or real time PCR. Nucleotide sequences of the VP4 region were used for genotyping and phylogenetic tree construction.


RESULTS
In total, 87 of 289 specimens were positive for HRV indicating an annual prevalence of 30%. Wheezing or asthma exacerbation was the most common clinical presentation observed in infected patients. Sequence analysis and phylogenetic tree showed that 29 (33%) and 8 (9%) specimens belonged to HRV-A and HRV-B, respectively. Most of the HRV positive samples were HRV-C (58%). Moreover, species C was predominantly found in the paediatric population of Thailand in raining season (p<0.05). The frequency of co-infection of HRV-C with other respiratory viral pathogens was approximately 40%.


CONCLUSIONS
HRV-C represents the predominant species and is one of the etiologic agents in acute lower respiratory tract infection, causes of wheezing and asthma exacerbation in infants and young children in Thailand.
Linsuwanon
Piyada
P
Center of Excellence in Clinical Virology, Department of Paediatrics, Chulalongkorn University, Rama IV, Patumwan, Bangkok 10330, Thailand.
Payungporn
Sunchai
S
Samransamruajkit
Rujipat
R
Posuwan
Nawarat
N
Makkoch
Jarika
J
Theanboonlers
Apiradee
A
Poovorawan
Yong
Y
D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008969:Molecular Sequence Data; D009305:Nasopharynx / Q000821:virology; D010802:Phylogeny; D010850:Picornaviridae Infections / Q000453:epidemiology* / Q000821:virology*; D016133:Polymerase Chain Reaction / Q000379:methods; D015995:Prevalence; D012367:RNA, Viral / Q000235:genetics; D012141:Respiratory Tract Infections / Q000453:epidemiology* / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012229:Rhinovirus / Q000145:classification* / Q000302:isolation & purification*; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D013785:Thailand / Q000453:epidemiology
D012367:RNA, Viral