Northwestern Medicine hospitals in Huntley, McHenry and Woodstock implemented a visitor management plan Tuesday in response to a rise in hospitalized patients with influenza. Dr. Irfan Hafiz – chief medical examiner for Northwestern Medicine’s Huntley, McHenry and Woodstock hospitals – said influenza management plans are in place every year and are implemented when it is deemed appropriate. When the visitor restrictions are initiated depends in the number of influenza cases nationally, regionally and locally as well as the number of cases that are seen at sister hospitals.