HIPAA covered entities, including employer sponsored health plans, and their business associates, must train employees who have access to protected health information.
Moreover, recent HIPAA settlement agreements with the Office of Civil Rights (OCR) have emphasized the importance of updating training materials and providing regular training to employees.
See here for a recent settlement along those lines: Yakima Valley Memorial Hospital Resolution Agreement and Corrective Action Plan | HHS.gov
If it has been some time since you last conducted a live training, consider that as an enhanced form of compliance. Your privacy/ERISA counsel can provide training in-person or remotely.
A well-crafted training program might include real life stories of breaches that have been experienced by others, which can help create a culture of compliance and make it easier for employees to identify ways to catch problems before they occur.