Environmental Survival of Avian Metapneumovirus on Common Agricultural Surfaces

Avian metapneumovirus (aMPV) is a major respiratory pathogen of poultry worldwide. While it is known to be transmitted through the air, the contribution of surface contamination to viral spread is unknown. This study evaluated the environmental survival of two viral subtypes on nine surfaces commonly found in agricultural settings, at two temperatures. Several issues contributed to the complexity of the analysis. In particular, the observed rate of decay was clearly non-linear and so a simple exponential model was not appropriate. Instead, Weibull curves were fit, and the area under the curve (AUC) was used as an overall measure of survival. A parametric bootstrap was then used to obtain standard errors and the survival on the various surfaces was compared using Wald tests. Additionally, the experimental design was suboptimal, so some desired comparisons were not able to be made. This talk will discuss the pros and cons of the experimental design and the chosen analysis and hopefully elicit feedback on alternative options.