Detection and genetic evolution of adenovirus from children with acute respiratory tract infections
10.3760/cma.j.issn.1674-2397.2016.01.005
- VernacularTitle:儿童急性呼吸道感染病例样本中腺病毒感染特征及遗传进化研究
- Author:
Yinyan ZHOU
;
Xinfen YU
;
Yu KOU
;
Jun LI
;
Xin QIAN
- Publication Type:Journal Article
- Keywords:
Adenovirus,human;
Respiratory tract infection;
Child;
Co-infection;
Genotype
- From:
Chinese Journal of Clinical Infectious Diseases
2016;(1):24-31
- CountryChina
- Language:Chinese
-
Abstract:
Objective To detect adenovirus from children with acute upper/lower respiratory tract infections and to investigate the genetic evolution of virus .Methods A total of 1 178 clinical specimens were collected from the Children ’ s Hospital , Zhejiang University School of Medicine during March 2011 and February 2013, including 513 throat swabs from children with acute upper respiratory tract infection and 665 nasopharyngeal aspirates from children with acute lower respiratory tract infections .Besides, 9 specimens in an outbreak of adenovirus infection during 2011 and 2014 were also collected .Adenovirus was identified by real-time fluorescent polymerase chain reaction (RT-qPCR).The hypervariable region (HVR)-7 region of hexon gene in positive samples was amplified and sequenced for typing and phylogenetic analysis .Other respiratory viruses were also detected with RT-qPCR in adenovirus positive samples .Clinical characteristics of adenovirus infection were analyzed in children with lower respiratory tract infections .Chi-square test and Fisher exact probability were used for data analysis .Results Among 1 178 samples from sporadic cases , 104 samples (8.83%) were adenovirus positive .The rates of adenovirus infection in upper respiratory tract infection group and lower respiratory tract infection group were 13.65%(70/513) and 5.11%(34/665), respectively (χ2 =26.193, P<0.05).Compared with that in lower respiratory tract infections , positive rates of adenovirus were higher in upper respiratory tract infections in children aged 0-1 year and >3 years (χ2 =6.575 and 7.334, P<0.05 or <0.01).Adenovirus infection might occur throughout the year and peaked in spring and summer .Among 54 adenovirus-positive samples from 104 sporadic cases , adenovirus types 1, 2, 3, 4, 7 and 31 were identified in 4, 6, 26, 2, 15 cases and 1 case, respectively.While among 9 adenovirus-positive samples from outbreak cases , type 4 and type 3 were identified in 1 and 8 cases, respectively .The HVR-7 region of hexon gene was highly homologous in the same type , and the sequence alignment indicated that the sequence of HVR-7 might have regional differences .Nine out of 70 children (12.86%) were co-infected with other virus in upper respiratory tract infection group , while the rate of co-infection in lower respiratory tract infection group was much higher [58.82%(20/34), χ2 =24.045, P<0.05 ].There was no significant difference in clinical manifestations between children infected with adenovirus only and those with co-infection in lower respiratory tract infection group (P>0.05), but two children with co-infection died.Conclusions Adenovirus infection is more common in upper respiratory tract infection .Adenovirus type 3 and type 7 are the most prevalent serotypes in sporadic cases , while type 3 is the most prevalent serotype in outbreak cases .