Inhibits host immune defense by binding to host chemokines. Binds host CC chemokines (beta chemokines) such as RANTES with high affinity, but not CXC or C chemokines (alpha and gamma chemokines). Binds to host CC chemokines, such as RANTES/CCL5, MIP-1alpha/CCL3, MCP-1/CCL2 and eotaxin. Belongs to the poxviridae chemokine-binding protein family.