Highly Pathogenic Avian Influenza A(H5N1) Viruses at the Animal–Human Interface in Vietnam, 2003–2010

Abstract

Mutation and reassortment of highly pathogenic avian influenza A(H5N1) viruses at the animal-human interface remain a major concern for emergence of viruses with pandemic potential. To understand the relationship of H5N1 viruses circulating in poultry and those isolated from humans, comprehensive phylogenetic and molecular analyses of viruses collected from both hosts in Vietnam between 2003 and 2010 were performed. We examined the temporal and spatial distribution of human cases relative to H5N1 poultry outbreaks and characterized the genetic lineages and amino acid substitutions in each gene segment identified in humans relative to closely related viruses from avian hosts. Six hemagglutinin clades and 8 genotypes were identified in humans, all of which were initially identified in poultry. Several amino acid mutations throughout the genomes of viruses isolated from humans were identified, indicating the potential for poultry viruses infecting humans to rapidly acquire molecular markers associated with mammalian adaptation and antiviral resistance.

Epidemiology of severe cases of influenza and other acute respiratory infections in the Eastern Mediterranean Region, July 2016 to June 2018

“…The unpredictable, continuous and rapid mutational potential of influenza viruses poses a serious threat to global health security with a possibility of pandemics at any time [4]. The zoonotic strains of influenza such as influenza A(H5N1) first detected in humans in 1997 in Hong Kong and then reported widespread globally since 2003, A(H7N9) reported in humans since 2013 in China and A(H9N2) reported for decades to be circulating in poultry and recently reported in humans, are strong evidence of these mutational capabilities; [5][6][7][8]. Therefore, influenza surveillance is essential to monitor and rapidly detect the circulation of different influenza viruses and the emergence of genetic changes in these viruses in humans and animals [9].…”

Regulation of Early Host Immune Responses Shapes the Pathogenicity of Avian Influenza A Virus

“…Influenza virus is a long-term threat to global public health. In contrast to human influenza A viruses (IAV) such as H1N1 (Du et al, 2017) that usually causes seasonal epidemic every year, avian IAV such as H5N1 (Creanga et al, 2017; Peng et al, 2017) and H7N9 (Wu et al, 2013) suddenly jump from their avian hosts to human and cause a high mortality rate, about 60% for H5N1 and 38% for H7N9 (Yu et al, 2008; Gao et al, 2013), which has brought serious social panic (Su et al, 2015). In order to improve the ability to control avian IAV, there is an urgent need for a deep understanding of their pathogenicities.…”

Two Live Attenuated Vaccines against Recent Low–and Highly Pathogenic H7N9 Influenza Viruses Are Safe and Immunogenic in Ferrets

“…Currently, there is a large reservoir of influenza A viruses among animals and birds. A number of different subtypes of animal influenza A viruses have infected humans, including Hsw1N1 [29], H5N1 [6,30,31], H5N6 [32,33,34], H6N1 [35], H7N3 [36,37,38], H7N4 [39], H7N7 [40,41,42], H7N9 [5,43,44,45,46], H9N2 [6,47,48] and H10N8 [49,50].…”