Porcine reproductive and respiratory syndrome virus (PRRS) is still one of the swine disease
s responsible for large economic losses in the US, despite of preventive and control measures implemented to reduce transmission within and between production systems. However, few studies have investigated how the different PRRSV genotypes are spreading among swine systems in the US and which are the most likely transmission pathways contributing to it.
The aim of this study is to estimate the specific role of direct (i.e., animal movements) and indirect (e.g., airborne or local spread) transmission of PRRSV genotypes within and between different swine production systems in the US.