Molecular characterization of avian metapneumovirus subtype C detected in wild mallards ( Anas platyrhynchos ) in The Netherlands

Abstract

Avian metapneumovirus (AMPV) represents a long-term threat to the poultry industry due to its etiological role in the induction of acute respiratory disease and/or egg drop syndrome in domestic turkeys, chickens, and ducks. Although this disease is commonly referred to as turkey rhinotracheitis, the host range of AMPV encompasses many avian species. We have screened 1323 oropharyngeal-and cloacal swab samples obtained from wild mallards in the Netherlands from 2017 to 2019 by RT-PCR using a degenerate primer pair to detect all members of the Paramyxoviridae and Pneumoviridae or an avian metapneumovirus subtype C (AMPV-C)-specific RT-qPCR assay.We identified a total of seven cases of AMPV-C infections in wild, healthy mallards (Anas platyrhynchos), of which two AMPV-C positive samples were further processed using next-generation sequencing. Phylogenetic analysis of the two complete genomes showed that the newly identified AMPV-C strains share closest sequence identity (97%) with Eurasian lineage AMPV-C strains identified in Muscovy ducks in China that presented with severe respiratory disease and egg production loss in 2011. Further analysis of G protein amino acid sequences showed a high degree of variability between the newly identified AMPV-C variants. PONDR scoring of the G protein has revealed the ectodomain of AMPV-C to be partitioned into a long intrinsically disordered and short ordered region, giving insights into AMPV G protein structural biology.In summary, we provide the first report of full-length AMPV-C genome sequences derived from wild birds in Europe. This emphasizes the need for further surveillance efforts to better characterize the host range, epidemiologic distribution, and pathogenicity of AMPV-C to determine the risk posed by cross-species jumps from wildfowl to domesticated avian species.

Longitudinal Survey on aMPV Circulation in French Broiler Flocks following Different Vaccination Strategies

“…aMPV-C natural infection in chickens has been reported only once, in China [40]. The circulation of these 'neglected' subtypes in chicken and turkey flocks should be explored in the future by implementing dedicated molecular diagnostic assays in cases of aMPV suspicion, in the light of the growing report number of aMPV-C detection in minor poultry species and wild birds [41][42][43][44][45][46][47][48], playing a possible epidemiological role. In the present study, vaccination against aMPV was applied to five out of seven broiler flocks, and protocols varied in terms of vaccine strain (strain 11/94 vs. strain PL21) and age of administration (at 1 day old at the hatchery or at the farm or at 7 days of age).…”

Establishment and Application Prospect of Reverse Transcriptase Recombinase-Aided Amplification Assay for Subgroup C Avian Metapneumovirus

“…In 1978, aMPV was found in South Africa and has since been widespread worldwide. As of now, aMPV has been found in many areas where poultry is raised in Europe, Asia, South America, Africa, and North America [ 8 , 9 , 10 , 11 , 12 , 13 ]. It can be seen that aMPV has an extensive spread range.…”

Detection and Genome Sequence Analysis of Avian Metapneumovirus Subtype A Viruses Circulating in Commercial Chicken Flocks in Mexico

“…The aMPV-A and -B viruses are widespread globally (except in North America and Australia). aMPV-C (consisting of North American and Eurasian lineages) was endemic in turkeys in the North Central USA before a successful eradication program, but it is likely endemic in some wild avian species; aMPV-C has recently been reported in wild mallards in the Netherlands and Italy [ 35 , 36 ]. Sporadic detections of aMPV-C in some avian species of minor economic importance (e.g., Muscovy duck and pheasant) in South Korea, China, and France, and aMPV-D in farmed turkey flocks in France, have also been reported [ 2 , 21 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ].…”