Co-infection of vvMDV with multiple subgroups of avian leukosis viruses in indigenous chicken flocks in China.

A co-infection of vvMDV with multiple ALV subgroups emerged in a chicken flock with neoplastic disease in Guangdong Province. The co-infection with different subgroups of ALV with vvMDV in one chicken flock poses the risk for the emergence of novel ALVs and heavily burdens the control strategy for MDV.