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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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Background and Objectives: Since 1997 National Institute of Virology, Bangalore Unit involved in WHO's Acute flaccid paralysis paediatric cases surveillance programme to isolate and detect polioviruses. Stool samples yielded not only polioviruses but also Non-Polio enteroviruses. This report is an overview of non‑polio Enterovirus (NPEV) epidemiology in Karnataka state, India for the period of 16‑years and 6 months from July 1997–2013. Methods: A total of 19,410 clinical samples were processed for virus isolation as a part of acute flaccid paralysis (AFP) surveillance for Global Polio Eradication Programme in India at National Polio Laboratory, at Bengaluru. NPEV detection was performed by virus isolation on cell culture according to World Health Organisation recommended protocols. Results: A total of 4152 NPEV isolates were obtained. The NPEV isolation rate varied from year to year but with a total NPEV rate of 21.39%. Conclusion: A seasonal variation was noted with high transmission period between April and October with peaks in June–July. The male to female ratio was 1:1.2. The isolation of NPEV decreased significantly with the increase in age. Epidemiology of NPEVs from AFP cases in Karnataka is described.
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Objective To investigate the virus-carrying rate of non-polio enteroviruses ( NPEV) in patients with acute flaccid paralysis ( AFP) in Yunnan province of China in 2015 and to analyze the genetic characteristics of enterovirus 71 (EV71) strains. Methods A total of 213 cases under 15 years old with AFP were reported by Center for Disease Control and Prevention ( CDC) of Yunnan Province of China. Virus isolation was conducted for all samples and the serotypes of isolated NPEV strains were identified by VP1 se-quencing. The isolation rates of NPEV in the past consecutive 5 years were analyzed by SPSS22. 0 software. Phylogenetic trees of NPEV and EV71 strains were constructed by MEGA6. 06 software based on neighbor-joining algorithm and Kimura 2-parameter substitution model and the reliability of the phylogenetic trees was determined by bootstrap analysis with 100 pseudo replicate datasets. Results Altogether, 23 NPEV strains were isolated from 213 AFP cases. Among the 23 strains, 7 strains belonged to EV-A group (2 serotypes, 6 strains of which were EV71 ) , 14 strains belonged to EV-B group ( 8 serotypes ) and the other 2 strains belonged to EV-C group. No NPEV strains of EV-D group were identified. Statistical analysis showed that no significant differences in the isolation rates were observed in the past 5 years ( P=0. 101 ) . Conclusion The isolation rate of NPEV in patients with AFP in Yunnan province in 2015 was similar to that of the previ-ous years. The EV71 strains of C4 subgenotype were the predominant strains circulating in Yunnan province.