A virulent bioluminescent and fluorescent dual-reporter Marek's disease virus unveils an alternative spreading pathway in addition to cell-to-cell contact.

Marek's disease virus (MDV) is a growing threat for the poultry industry. Unfortunately, despite successful vaccination against the disease, MDV remains in circulation within vaccinated flocks, leading to the selection of increasingly virulent pathotypes. Detailed knowledge of the virus biology and the host-virus interaction is required to improve the vaccine efficiency. In the present study, I engineered an original, dual-reporter MDV to track and quantify virus replication in vitro and in vivo.