Amerigroup Washington a wholly owned subsidiary of Anthem, Inc. Medicaid provider in the North Central Region, was selected by the Washington State Health Care Authority to provide fully integrated managed care for Medicaid members residing in the counties of Chelan, Douglas and Grant. The contract is an extension of the services Amerigroup already provides to Medicaid eligible populations in the North Central region. These integrated benefits will become available to members January 1, 2018.