A Novel H1N2 Influenza Virus Related to the Classical and Human Influenza Viruses from Pigs in Southern China.

Yafen Song,Nannan Qu,Guowen Ouyang,Yan Qi,Xiaowei Wu,Jin Cui,Peirong Jiao,Ming Liao,Nianchen Wang

doi:10.3389/fmicb.2016.01068

Abstract

Southern China has long been considered to be an epicenter of pandemic influenza viruses. The special environment, breeding mode, and lifestyle in southern China provides more chances for wild aquatic birds, domestic poultry, pigs, and humans to be in contact. This creates the opportunity for interspecies transmission and generation of new influenza viruses. In this study, we reported a novel reassortant H1N2 influenza virus from pigs in southern China. According to the phylogenetic trees and homology of the nucleotide sequence, the virus was confirmed to be a novel triple-reassortant H1N2 virus containing genes from classical swine (PB2, PB1, HA, NP, and NS genes), triple-reassortant swine (PA and M genes), and recent human (NA gene) lineages. It indicated that the novel reassortment virus among human and swine influenza viruses occurred in pigs in southern China. The isolation of the novel reassortant H1N2 influenza viruses provides further evidence that pigs are “mixing vessels,” and swine influenza virus surveillance in southern China will provide important information about genetic evaluation and antigenic variation of swine influenza virus to formulate the prevention and control measures for the viruses.

Highlights

China is the biggest country for swine breeding and pork production, and the largest market for the consumption of pork in the world
The virus was isolated from nasal swab samples of nursery pigs, and identified by the reverse-transcription polymerase-chain reaction (RT-PCR), hemagglutination test, and hemagglutination inhibition (HI) test and confirmed by genomic sequencing and the nucleotide BLASTn analysis
This is known as the “classical” H1N1 swine virus

Summary

Introduction

China is the biggest country for swine breeding and pork production, and the largest market for the consumption of pork in the world. As the RNAdependent RNA polymerase could not proofread the newly synthesized gene segments, mutations of influenza A viruses arise in each replication cycle (Nichol et al, 2000; Koçer et al, 2013). It comes as no surprise; the viruses never stop changing and generating new viral subtypes via mutation, recombination and reassortant. Novel H1N2 Influenza Virus from Pigs special breeding environments and features of the virus result in various subtypes and genotype coexisting in China, which would accelerate the genomics evolutionary and antigenic variation of swine influenza viruses. Virologic and serologic surveillance of swine influenza virus is urgently required

Methods

Results

Conclusion