Well, there is/was an open source EHR called Vista and VA uses it. However, even that is being replaced by VA at a cost of $10 Billion over 10 years to Cerner (

Well, there is/was an open source EHR called Vista and VA uses it. However, even that is being replaced by VA at a cost of $10 Billion over 10 years to Cerner (https://www.ehrm.va.gov/news/article/alias/va-signs-contract-with-cerner-for-an-electronic-health-record-system https://www.ehrm.va.gov/news/article/alias/va-signs-contract...)