Assessment of contemporary genetic diversity and inter-taxa/inter-region exchange of avian paramyxovirus serotype 1 in wild birds sampled in North America

Abstract

Background: Avian paramyxovirus serotype 1 (APMV-1) viruses are globally distributed, infect wild, peridomestic, and domestic birds, and sometimes lead to outbreaks of disease. Thus, the maintenance, evolution, and spread of APMV-1 viruses are relevant to avian health. Methods: In this study we sequenced the fusion gene from 58 APMV-1 isolates recovered from thirteen species of wild birds sampled throughout the USA during 2007-2014. We analyzed sequence information with previously reported data in order to assess contemporary genetic diversity and inter-taxa/inter-region exchange of APMV-1 in wild birds sampled in North America. Results: Our results suggest that wild birds maintain previously undescribed genetic diversity of APMV-1; however, such diversity is unlikely to be pathogenic to domestic poultry. Phylogenetic analyses revealed that APMV-1 diversity detected in wild birds of North America has been found in birds belonging to numerous taxonomic host orders and within hosts inhabiting multiple geographic regions suggesting some level of viral exchange. However, our results also provide statistical support for associations between phylogenetic tree topology and host taxonomic order/region of sample origin which supports restricted exchange among taxa and geographical regions of North America for some APMV-1 sub-genotypes. Conclusions: We identify previously unrecognized genetic diversity of APMV-1 in wild birds in North America which is likely a function of continued viral evolution in reservoir hosts. We did not, however, find support for the emergence or maintenance of APMV-1 strains predicted to be pathogenic to poultry in wild birds of North America outside of the order Suliformes (i.e., cormorants). Furthermore, genetic evidence suggests that ecological drivers or other mechanisms may restrict viral exchange among taxa and regions of North America. Additional and more systematic sampling for APMV-1 in North America would likely provide further inference on viral dynamics for this infectious agent in wild bird populations.

Global phylodynamic analysis of avian paramyxovirus-1 provides evidence of inter-host transmission and intercontinental spatial diffusion

“…For example, previous research efforts support the exchange of virus between wild and domestic flocks, including the diffusion of live vaccine strains intended for domestic poultry into wild birds [10,11]. The majority of APMV-1 maintained in wild birds are predicted to be avirulent in gallinaceous poultry [2,12], but experimental evidence has shown that multiple passages of avirulent wild APMV-1 in chickens can produce virulent APMV-1 strains [13]. APMV-1 of low virulence are capable of evolving naturally into a virulent phenotype; however, this has been documented only occasionally [14,15].…”

Phylogeny, pathogenicity and transmissibility of a genotype XII Newcastle disease virus in chicken and goose

“…Although all NDV strains are categorized as a single serotype, they can be divided into two clades, class I (1a–d) and class II (I–XVIII) (Ramey et al, ; Snoeck et al, ), based on the classification system for assigning NDV isolates recommended by Diel, Silva, et al (). The classification criteria based on the phylogenetic tree topology of the complete nucleotide sequences of the F gene constructed using the maximum likelihood (ML) method with a nodal bootstrap value >60%.…”

Characterization of a Novel Avian Avulavirus 1 of Class I isolated from a Mute Swan (Cygnus Olor) in Macedonia in 2012

“…Due to increasing availability of sequencing techniques and sequences included from previously unreported areas, new genotypes/ subgenotypes are being identified frequently (4,5). Nowadays, based on the complete F gene sequence, class I consists of one genotype further divided into four subgenotypes (1a, 1b, 1c and 1d), while class II consists of 18 genotypes, some of them further divided into subgenotypes (4,5,6). The presence of viruses that are unassigned to any of the four genotypes (4,6,7,8), combined with the addition of novel viruses may lead towards an extension of the current classification of the class I viruses by designating new subgenotypes.…”

“…Nowadays, based on the complete F gene sequence, class I consists of one genotype further divided into four subgenotypes (1a, 1b, 1c and 1d), while class II consists of 18 genotypes, some of them further divided into subgenotypes (4,5,6). The presence of viruses that are unassigned to any of the four genotypes (4,6,7,8), combined with the addition of novel viruses may lead towards an extension of the current classification of the class I viruses by designating new subgenotypes. According to the criteria set for the establishment of a new genotype/subgenotype (4), these unassigned viruses possess a sufficient evolutionary distance for the designation of new subgenotype but other independent isolations of viruses with separate epidemiological background lack.…”

“…Majority of isolations of class I viruses comes from waterfowl and domestic poultry from live bird markets in the USA, China and Hong Kong (9,10,11,12), although isolations from wild birds are reported in Europe, USA, China, Russia, and Japan (5,6,7). The vast majority of these viruses are avirulent (8,9,11,12,13) and because of their low virulence they do not fall under the OIE criteria for declaring a ND outbreak, i.e.…”