| Background ﹠ Aims: Respiratory tract infection refers to a group of diseases,mainly caused by pathogenic microorganisms invading the respiratory tract,and the body’s resistance is not enough to resist infection.In patients with respiratory tract infection,HRV infection occupies a larger proportion.Previous studies believed that rhinovirus would only lead to relatively benign upper respiratory tract disease,and its attention was relatively low.But as research into rhinoviruses continues to unfold,rhinoviruses have been found to be associated with worsening chronic lung disease,the development of asthma,severe bronchiolitis,and fatal pneumonia in older and immunocompromised adults.Therefore,international societies such as the United States,Japan,South Korea and Kenya,and in Guangzhou,Shanghai,Hong Kong,Gansu,Beijing,Changsha and other regions of China have studied the infection of rhinovirus in respiratory infections,but in Qingdao,China,for rhinovirus The epidemic characteristics of rhinovirus and the full-length sequence of rhinovirus in China are rarely reported.This study took 328 patients with respiratory tract infections in Qingdao in the autumn and winter of 2020 as the research objects to study the infection of rhinoviruses and to isolate and identify rhinoviruses,in order to provide reference for future research on rhinoviruses in respiratory tract infections in Qingdao.It provides material support for the vaccine research of Chinese rhinovirus and the biological properties of the virus,and can provide a reference whole genome sequence for the evolution and mutation research of rhinovirus.Methods: The research subjects of this study were collected from 328 patients with respiratory tract infection entrusted by the Institute of Viral Diseases of the Chinese Center for Disease Control and Prevention,Qingdao CDC,from September 2020 to February 2021.Nucleic acids were extracted from328 throat swab samples from patients,and the nucleic acids extracted from the samples were screened for 15 common respiratory viruses by fluorescence quantitative PCR.The HRV-VP4/VP2 gene was amplified and sequenced by nested PCR for the samples that were initially screened for human rhinovirus,and the obtained sequences were subjected to phylogenetic tree and homology analysis.The positive samples were screened for virus isolation.For the samples with successful virus isolation,the nucleic acid after virus isolation was extracted,and the virus was identified by fluorescence quantitative PCR and nested PCR,and the complete genome sequence of the successfully isolated rhinovirus was determined.Results: 1.Among 328 patients with respiratory tract infection,15 respiratory viruses were screened,and at least one respiratory virus was detected in 121 cases,with a virus detection rate of 36.88%.The detection of a single virus showed that the detection rate of HRV was 10.37%(34/328),RSV and h MPV were both 3.66%(12/328),HCOV-NL63 was 2.74%(9/328),HBOV and ADV were All were2.44%(8/328),1.83%(6/328)for both PIV1 and HEV,1.22%(4/328)for hcov-HKU1 and 0.30%(1/328)for PIV2,OC43 and FLUA.2.Among HRV-positive patients,the detection rate of male patients was higher than that of female patients,but the difference between the two was not statistically significant.HRV had the highest detection rate in the 0-15-year-old group.In autumn,the detection rate of HRV was higher than that in winter,and the difference was statistically significant.3.Among the 45 HRV-positive patients,11 patients had mixed infection with other viruses,mainly the mixed infection of HRV and RSV,accounting for 45.45%.4.Amplify the target fragment of HRV-VP4/VP2 in 45 HRV-positive patients to obtain 38 HRV strain sequences,including HRV-A,B and C groups,including 28 HRV-A strains(including A36,A53 are 4 strains,A28 is 3 strains,A15 and A01 are 2 strains,A20,A58,A49,A78,A07,A21,A55,A32,A09,A41,A16,A47,A40 are all 1 strain),8 HRV-C(including 3 C45 and C03,C06,C15,C40,C48 are all1)and 2 HRV-B(all B52)5.The 38 HRV sequences obtained in our laboratory,in HRV-A group,the nucleotide and amino acid homology between the sequences is 66.4-98.7% and 86.3%-100% respectively;in HRV-C group In the HRV-B group,the nucleotide and amino acid homology between the two sequences was 64.7-97.9%and 78.6-100%,respectively;in the HRV-B group,the nucleotide and amino acid homology between the two sequences was 96.8%,respectively and 100%.6.The genome of QD1040 strain is 7141 nt in full length,which is rhinovirus A28 type.It has the closest genetic distance to the newly reported full-length 2021 US strain(Gene Bank No.:MZ629129.1),with a nucleotide homology of 98.7%.Compared with it,93 bases were mutated,and8 amino acid positions were changed.The genome of HRV QD1078 strain is 7138 nt in length,and it is rhinovirus A58.The results of the full-length phylogenetic tree of the genome showed that the genetic distance to the 2008 American strain(Gene Bank No.: FJ445142.1)was the closest,and the nucleotide homology was 97.2%.Compared with it,220 bases were mutated,of which 15 amino acid positions were changed.Conclusion: 1.Rhinovirus is the main viral pathogen of patients with respiratory tract infections in Qingdao in the autumn and winter of 2020,and HRV-A infection is the main type.The prevention and control of rhinovirus in this area should be strengthened.2.There are 25 rhinovirus serotypes in the sequences of 38 HRV strains.The existence of multiple serotypes may recombine to generate new rhinovirus strains,which requires further research on rhinovirus.3.The two rhinovirus isolates obtained in this experiment are HRV-A28 and HRV-A58,respectively.Rhinoviruses are prone to mutation compared to their genetically closest reference strains,and care should be taken to guard against the possibility of rhinoviruses producing highly pathogenic strains.Figure [12] Table [11] Reference [59]... |
PDF Full Text Request