RESUMO
Objective To understand the epidemiologic feature of human parainfluenza virus type 3 (HPIV-3) in Shanghai,and to provide scientific evidence for formulating prevention and control measures in the future.Methods A total of 164 nasopharyngeal aspirates samples taken from children with acute respiratory infection (ARI) were collected from Xinhua Hospital Affiliated to Shanghai Jiaotong University and sent to Shanghai Public Health Clinical Center from June 2009 to June 2010.Samples were detected for HPIV-3 by reversed transcription-polymerase chain reaction (RT-PCR).Full-length hemagglutininneuraminidase (HN) gene (1 719 bp) of five positive samples were sequenced for phylogenetic analysis.Comparison between two groups was evaluated by the precise chi-square test (two sided).Results Of 164 samples,70 samples were infected with parainfluenza virus,and HPIV-3 was detected positive in 23 samples with the positive rate of 32.86％.HPIV-3 infections were most common in spring and summer,and most of infections were mainly found in 13-36 month-old infants.Five Shanghai isolates and 36 reference sequences from different countries and areas were divided by HN gene-based phylogenetic tree into three clusters (A,B and C).Five Shanghai isolates and five Beijing isolates belonged to C3a group.The homologies of nucleotide and amino acid sequences between five Shanghai isolates and five Beijing isolates were 99.0％-99.5％ and 99.7％-100.0％,respectively.Conclusions HPIV-3 accounts for a high proportion in children with ARI in Shanghai.C3a group may be the main lineage of HPIV-3,which suggests that HPIV-3 may be of regionally correlation.
RESUMO
Objective To explore the situation of respiratory virus co-infection with EV71 and CA16 in patients with hand,foot and mouse disease(HFMD) ,and analyze the influence of co-infection on clinical aspects.Methods From June to October of 2010,there were 348 patients enrolled in the study,with 248 hospitalization cases and 100 mild outpatients.All the patients were diagnosed as HFMD in Beijing You-an Hospital.The viral RNA from the pharynx swab samples were extracted and reversely transcribed by RT-PCR.All the samples were detected with the EV71 and CA16 by real-time fluorescence quantitative PCR.Twelve kinds of respiratory viruses were detected by a commercial multiplex-PCR method.The PCR products were confirmed by electrophoresis.Chi square test was used in the data analysis.Results Of the 348 HFMD patients,36 subjects were detected as positive for respiratory virus co-infection.In the 248 hospitalization cases,111 cases were positive for EV71 or CA16,with eight cases identified with respiratory virus co-infection(7.2%); the other 137 cases were negative for EV71 and CA16,with eleven cases identified with respiratory virus co-infection(7.4%).There was not significant difference between respiratory virus co-infection and the identification of EV71 /CA16(x2 = 0.059,P ＞ 0.05).In the 100 mild outpatients positive for EV71 or CA16,seventeen cases were identified with respiratory virus co-infection(17%).The rate of respiratory virus co-infection in the mild outpatients was much higher than in the severe hospitalization patients(x2 = 4.830,P＜ 0.05).Among the 111 EV71(+) or CA16(+) inpatients,there were 101 cases diagnosed as severe cases(91.0%); similarly,there were 132 cases diagnosed as severe cases(96.4%) among the 137 EV71(-) CA16(-) cases.There was not difference between the identification of EV71/ CA 16 and illness of HFMD(x2 = 3.099,P ＞ 0.05).The leading respiratory virus being identified were HRV A/B,PIV3 and FLU A in the 348 HFMD patients.Conclusions Co-infection with respiratory virus exists in the HFMD patients. However,the respiratory virus infection has no significant influence to the state of HFMD illness.