Epidemiological Study Of Human Parainfluenza Viruses In Outpatients In Shanghai,China

Part 1 Epidemiological study of Human Parainfluenza Viruses in Shanghai from 2009 to 2010 and Genetic Characterization of HPIV-3ObjectiveTo investigate the epidemiological characteristics of Human Parainfluenza Viruses in Shanghai China.Subjects and MethodsOne hundred and sixty-four nasopharyngeal swabs were collected from children with upper respiratory infection symptoms i.e. fever cough runny nose and sore throat, in the fever clinic of Xinhua Hospital affiliated to Shanghai Jiao Tong University from June 7,2009 to June 5,2010.Mutiplex RT-PCRs were used to screen respiratory viruses including HPIVl-4.The ration, genders and age of patients were recorded. Seasonal distribution of HPIVs infections were aslo analyzed.For HPIV-3 positive samples, HPIV-3 HN genes were further amlpified by nest RT-PCR. Their sequences were analyzed by programs of Mega 5.0(Molecular Evolutionary Genetics Analysis), sequencer and DNAStar 6.0.ResultsAmong 164 nasopharyngeal swabs,78.7%(129/164) were positive for viruses. HPIVs were dominantly accounted for 42.7%(70/164). Out of 70 HPIV-positive samples,14 (8.5%,14/164) were positive for HPIV-1; 30 (18.3%,30/164) were positive for HPIV-2; 23 (14.0%,23/164) were positive for HPIV-3; 3 (1.8%,3/164) were positive for HPIV-4.About 45.7% (32/70) HPIVs infections were coinfected with other respiratory viruses. HPIVs had been detected from 74.1% (40/54) infants at 12-24 months old, whileas 9.7% (6/62) in infants younger than 12 months. There were statistically significant difference in HPIVs detection rate between age groups(χ2=50.408, P=0.000). Detection rates had shown no significant difference between male and female (χ2=1.844, P=0.204). HPIVs detection rates in spring (76.5%) and summer (42.7%) were higher than in autumn (32.3%) and winter (22.2%) (χ2=14.594, P=0.002).Nucleotide and amino acid homologies among five HPIV-3 Shanghai isolates were 99.0-99.5% and 99.7-100%, respectively. Compared to 11 HPIV-3 representative domestic isolates, homologies in nucleotide or amino acid sequences were 97.1-99.8% and 99.0-100%, respectively; Compared to HPIV-3 isolates from Japan (excluding GP), India and Saudi Arabia in Asia, homologies in nucleotide or amino acid sequences were 96.0-98.7% and 97.0-99.5%, respectively; Compared to HPIV-3 isolates from USA(excluding Oklahoma), Canada and Australia, homologies in nucleotide and amino acid sequences were 94.4-95.4% and 96.7-97.7%, respectively.Phylogenetic tree had revealed that 41 HPIV-3 isolates could be classified into three distinct clusters (A, B and C). Cluster C can be subsequently divided into four subclusters, C1-C4. Most of cluster C contained strains were isolated from Japan, India, Saudi Arabia and China during 2002 to 2010. This implied that cluster C was the predominant epidemic lineages of HPIV-3 and circulated in Asia. Five HPIV-3 Shanghai isolates were belonging to C3a together with Beijing isolates in 2008-2009. Nucleotide sequences (ShangHai.210 and BJ001/08), (ShangHai.1261 and BJ001/08) and (ShangHai.1431 and BJ005/08) were 99.6%,99.4% and 99.1%, respectively. However, there was not amino acid difference among them.ConclusionsHPIVs infection occupied an important status in infants and young children with respiratory tract infections in Shanghai. Incidence of HPIVs infections was 42.7%. Among 70 HPIVs-positive samples, HPIV-2 was the leading infected subtype, followed by HPIV-1 and HPIV-3.HPIVs infetions showed difference in age groups, but not in genders, distribution. They were predominated in spring and summer.Phylogenetic trees had shown that HPIV-3 shanghai isolates were clustered with domestic isolates, but not international isolates. They were regional circulated.Part 2 Meta-analysis on epidemiology of Parainfluenza Viruses infection among Chinese people from 1996 to 2013ObjectiveTo understand the epidemiologic features of parainfluenza viruse infection among Chinese people, help for diagnosis, prevention or treatment of PIVs associated diseases.Subjects and MethodsPublished papers on the epidemiology of parainfluenza viruses infection were retrieved from China National Knowledge Infrastructure, Chinese Science & Technology Journal Database,Wanfang Database and PubMed. Inclusion criteria was applied for selection of qualified papers. Meta-analysis was performed to estimate overall PIV infections in China.ResultsFifty-two papers were retrieved accounted for overall sample size at 186,053 people. Pooled infection rate of PIVs in China was 6.8%. Pooled infection rate of PIVs for children aged 0-3 years (≤1 year group 7.7% and 1-3 years group 8.9%) were higher than children aged>3 years (6.8%). No statistical difference was found in HPIVs infection for two genders. The pooled infection rates of PIVs for children with ARI in spring, summer, autumn and winter were 8.2%,8.0%,6.6% and 5.1%, respectively. For upper and lower respiratory tract infections, pooled infection rates of PIVs were 7.2% and 8.9% respectively. PIV infections can cause bronchitis (9.3%), pneumonia (8.2%), bronchopneumonia (8.7%), and bronchiolitis (7.1%).ConclusionsThe infection rates of PIVs for children with ARI were different in area; PIV infections had a negative correlation with age, but no relation with gender. PIVs were more often presented in spring and summer. Main diagnosis of PIV infections was acute lower respiratory infections, i.e. bronchitis, pneumonia, bronchopneumonia and bronchiolitis.