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Objective:To analyze the molecular characteristics of hemagglutinin-neuraminidase (HN) gene of human parainfluenza virus type 3 (HPIV3) among the cases with acute respiratory tract infection (ARI) in Henan Province.Methods:Nasal/throat swab samples collected from patients with severe acute respiratory tract infection (SARI) in Luohe and patients with influenza-like illness (ILI) in Zhengzhou were used in this study. HPIV nucleic acids in the samples were detected using real-time fluorescent PCR. HPIV3-positive samples were subjected to RT-PCR for the amplification of HN genes and the sequences were analyzed with Sanger method. CExpress and MEGA7.0 software were used for sequences editing, evolution tree construction and gene sequence analysis.Results:A total of 374 throat swab samples collected form ARI cases in Luohe and Zhengzhou were tested and 20 (5.3%) of them were positive for HPIV3. Eighteen HPIV3 HN gene sequences were successfully amplified and all belonged to C3 subgroups, including 16 sequences of C3f genotype and two sequences of C3a genotype. The 18 HN gene sequences shared the homology of 97.6%-100.0% in nucleotide and 99.3%-100.0% in amino acid, but the differences between them and the prototype strain Wash/47885/57 were significant. There were 12 amino acid mutations shared by them, including four function-related mutations (H295Y, I391V, D556N and I53T). There were no significant differences in the nucleotide or amino acid sequences as compared with the epidemic strain of China/BCH4210A/2014.Conclusions:The C3f and C3a branches of HPIV3 were the epidemic genotypes in Henan Province in recent years and a local circulating prevalence might be established. Continuous and in-depth monitoring of HPIV3 C3 subtype would be of great significance for the prevention and control of HPIV3-associated diseases.
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Objective:To analyze tetanus antibody levels in healthy people in Henan Province and to provide reference data for the adjustment of tetanus vaccine immunization strategy.Methods:A total of 7 519 healthy people were selected using stratified sampling in Henan Province from 2020 to 2021. Serum samples were collected and tested for anti-tetanus toxoid IgG antibody (anti-TT) by ELISA. The positive rate (≥0.01 IU/ml), protection rate (≥0.1 IU/ml) and mean concentration (MC) of anti-TT were analyzed.Results:The overall positive rate, protection rate and MC of anti-TT among the 7 519 subjects were 70.33% (5 288/7 519), 37.07% (2 787/7 519) and 0.035 IU/ml, respectively. Both basic and booster tetanus vaccines were effective. The positive rate, protective rate and MC of anti-TT decreased from 99.63% (272/273), 82.05% (224/273) and 0.215 IU/ml in 6-year-olds to 64.22% (262/408), 21.57% (88/408) and 0.023 IU/ml in 16- to 19-year-olds, and further decreased to 40.97% (1 302/3 178), 5.48% (174/3 178) and 0.007 IU/ml in people ≥20 years old.Conclusions:The level of tetanus antibody decreased with age in healthy people in Henan Province. It was suggested that the sixth dose of tetanus vaccine should to be given at 16-20 years old.
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Objective:To investigate the serotypes and epidemic characteristics of non-polio enteroviruses (NPEV) in acute flaccid paralysis (AFP) cases in Henan Province in 2021.Methods:Fecal specimens of 529 AFP cases reported in Henan Province in 2021 were collected for virus isolation. The VP1 regions of NPEV were sequenced. MEGA5.1 software was used for sequence alignment and a phylogenetic tree was constructed as well. The epidemiological data were organized and statistically analyzed using Excel2016 and SPSS26 software.Results:A total of 30 strains of NPEV were isolated from the fecal specimens of 529 AFP cases, with an isolation rate of 5.67% (30/529). They were belonged to group A and group B with 15 strains in each group, and no group C or group D viruses were isolated. Group A contained six serotypes and was dominated by coxsackievirus A2 (CVA2) and CVA6. Group B contained tree serotypes and was dominated by CVB3. In the population distribution, the separation rate of NPEV was the highest among children under 5 years old, which was 76.67% (23/30), and the ratio of male to female was 1.51∶1. In the regional distribution, group A viruses were mainly distributed in the central, southern and southwestern parts of Henan Province with CVA2 and CVA4 being the most widely distributed, while group B viruses were relatively concentrated, mainly distributed in the central, northern and southwestern parts of Henan Province with CVB3 being the predominant. In terms of time distribution, NPEV could be isolated throughout the year except from January to February, showing the epidemic characteristics of high incidence in spring and summer and low incidence in autumn and winter. The peak of group A virus infection was in May and the peak period of group B virus infection was from June to July.Conclusions:CVB3 was the main serotype of NPEV isolated in Henan Province in 2021. The pathogenic spectrum and regional distribution of NPEV had changed significantly compared with those in 2018-2019. In order to provide reference for the diagnosis and surveillance of AFP and maintain the polio-free status in Henan Province, much attention should be paid to the current epidemic trend of NPEV.
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Objective:To investigate the types and distribution of non-polio enterovirus (NPEV) in acute flaccid paralysis (AFP) cases in Henan Province in 2019.Methods:A total of 513 cases of AFP were reported in Henan Province in 2019. Two stool specimens were collected from each case for virus isolation. The VP1 gene of NPEV-positive strains was amplified and sequenced. Sequence alignment and construction of the phylogenetic tree were completed by MEGA5.1 software. The epidemiological data of NPEV-positive strains were statistically analyzed by Excel 2016 and SPSS19 software.Results:A total of 39 NPEV strains were isolated from 513 AFP cases, with an isolation rate of 7.60% (39/513). Among them, 18 strains were group A viruses and 21 strains were group B viruses. Both group A and group B viruses contained seven serotypes. No viruses of group C and group D was isolated. Coxsackievirus A type 4 (CVA4) and CVA16 were the predominant types in group A, and echovirus type 11 (Echo11) was the predominant type in group B. The nucleotide identity between the NPEV-positive strains was 67.4%-100.0%, and their nucleotide identity with the prototype strain was 71.4%-85.6%. NPEV was mainly detected in scattered children under 7 years old with an isolation rate of 84.62% (33/39), and the ratio of male to female was 2.07∶1. No statistically significant difference in the isolation rate was found between different age groups or between different sexes ( P>0.05). Among the group A viruses, CVA2, CVA4 and CVA16 were widely distributed. Echo3, Echo11 and Echo30 were the widely distributed group B viruses. NPEV could be isolated throughout the year except for January. Group A virus infections mainly occurred from April to July, accounting for 66.67% (12/18) of the whole year. Group B virus infections mainly occurred in September, accounting for 28.57% (6/21) of the whole year. Conclusions:The main serotype of NPEV isolated in Henan Province in 2019 was Echo11. The pathogen spectrum and regional distribution of NPEV as well as the isolation rate in different age groups changed significantly compared with those in 2018. Therefore, it was necessary to strengthen monitoring and conduct targeted prevention and control to effectively reduce the occurrence of AFP.
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Objective To standardize the reporting system on hepatitis B in order to improve the quality of monitoring program in Henan province.Methods A total of 6 sites of Hepatitis B pilot surveillance were selected in Xinzheng of Zhengzhou city,Linzhou of Anyang city,Shanyang district of Jiaozuo city,Shaoling district of Luohe city,Yongcheng of Shangqiu city,Pingqiao district of Xinyang city in Henan province.Subjects under study were those reported hepatitis B cases,from 2012 to 2016.Cases diagnosed in 2011 were chosen as controls.Data on classification of hepatitis B,time that HBsAg became positive and ALT value of the cases were analyzed annually.5 ml venous blood was collected and anti-HBc IgM confirmed test was made for those suspected acute cases on hepatitis B.Based on the 2016 data from the monitoring system,the incidence of acute hepatitis B in Henan province was estimated.Results The number of reported hepatitis B cases had declined in 6 sites of Hepatitis B pilot surveillance substantially.A total of 17 436 hepatitis B reported in 2011 but only 2 632 cases were reported in 2016,with a reduction of 84.90%(14 804/17 436) in these six monitoring sites.The number of unclassified hepatitis B cases also dropped sharply.In 2011,36.87% of the cases were unclassified,but the figure reduced to 0.08% in 2016,from the six sites.The rate on ALT detection also gradually improved.The rate of misdiagnosis on HBV carrier from hepatitis B almost disappeared.From 2013 to 2016,777 blood samples were collected from six pilot sites.29.34% (228/777) of the blood samples were tested positive for anti-HBc IgM after confirmed by the hepatitis laboratory of the China Center for Disease Control and Prevention.Conclusions Since the development of the pilot surveillance program,the quality of reporting system on hepatitis B had been improved,as well as the accuracy of diagnosis.Rate on the accuracy of reporting on hepatitis B and the methods of testing should be improved at the monitoring sites.
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Objective: To standardize the reporting system on hepatitis B in order to improve the quality of monitoring program in Henan province. Methods: A total of 6 sites of Hepatitis B pilot surveillance were selected in Xinzheng of Zhengzhou city, Linzhou of Anyang city, Shanyang district of Jiaozuo city, Shaoling district of Luohe city, Yongcheng of Shangqiu city, Pingqiao district of Xinyang city in Henan province. Subjects under study were those reported hepatitis B cases, from 2012 to 2016. Cases diagnosed in 2011 were chosen as controls. Data on classification of hepatitis B, time that HBsAg became positive and ALT value of the cases were analyzed annually. 5 ml venous blood was collected and anti-HBc IgM confirmed test was made for those suspected acute cases on hepatitis B. Based on the 2016 data from the monitoring system, the incidence of acute hepatitis B in Henan province was estimated. Results: The number of reported hepatitis B cases had declined in 6 sites of Hepatitis B pilot surveillance substantially. A total of 17 436 hepatitis B reported in 2011 but only 2 632 cases were reported in 2016, with a reduction of 84.90%(14 804/17 436) in these six monitoring sites. The number of unclassified hepatitis B cases also dropped sharply. In 2011, 36.87% of the cases were unclassified, but the figure reduced to 0.08% in 2016, from the six sites. The rate on ALT detection also gradually improved. The rate of misdiagnosis on HBV carrier from hepatitis B almost disappeared. From 2013 to 2016, 777 blood samples were collected from six pilot sites. 29.34% (228/777) of the blood samples were tested positive for anti-HBc IgM after confirmed by the hepatitis laboratory of the China Center for Disease Control and Prevention. Conclusions: Since the development of the pilot surveillance program, the quality of reporting system on hepatitis B had been improved, as well as the accuracy of diagnosis. Rate on the accuracy of reporting on hepatitis B and the methods of testing should be improved at the monitoring sites.