The survival of avian reoviruses on materials associated with the poultry house environment.

Two strains of avian reovirus were tested for their ability to survive on materials common to most poultry houses. The viruses survived longest and for at least 10 days on feathers, wood shavings and chicken feed, and for the shortest periods on wood (2 days), paper and cotton (4 days). There were some differences in survivability between the two strains.

Avian metapneumovirus SH gene end and G protein mutations influence the level of protection of live-vaccine candidates.

A prototype avian metapneumovirus (AMPV) vaccine (P20) was previously shown to give variable outcomes in experimental trials. Following plaque purification, three of 12 viruses obtained from P20 failed to induce protection against virulent challenge, whilst the remainder retained their protective capacity. The genome sequences of two protective viruses were identical to the P20 consensus, whereas two non-protective viruses differed only in the SH gene transcription termination signal.

Demonstration of loss of attenuation and extended field persistence of a live avian metapneumovirus vaccine.

A live A type avian metapneumovirus (AMPV) vaccine which had been shown to be highly protective and short lived in experimental conditions was found to persist for longer periods in the field and to be associated with disease. Previously other factors such as possible secondary pathogens and management considerations had made it impossible to conclude whether the observed disease was a result of an increase in the vaccine virulence. In this study, an AMPV was isolated from poults on a farm which had been vaccinated with the same live A type vaccine.

Design, validation, and absolute sensitivity of a novel test for the molecular detection of avian pneumovirus.

This study describes attempts to increase and measure sensitivity of molecular tests to detect avian pneumovirus (APV). Polymerase chain reaction (PCR) diagnostic tests were designed for the detection of nucleic acid from an A-type APV genome. The objective was selection of PCR oligonucleotide combinations, which would provide the greatest test sensitivity and thereby enable optimal detection when used for later testing of field materials.

Development of a reverse-genetics system for Avian pneumovirus demonstrates that the small hydrophobic (SH) and attachment (G) genes are not essential for virus viability.

Avian pneumovirus (APV) is a member of the genus Metapneumovirus of the subfamily Pneumovirinae. This study describes the development of a reverse-genetics system for APV. A minigenome system was used to optimize the expression of the nucleoprotein, phosphoprotein, M2 and large polymerase proteins when transfected into Vero cells under the control of the bacteriophage T7 promoter.