Overnight Health Care: House panels launch probe into Alzheimer's drug | Half of public health workers experiencing mental health strain | Puerto Rico presses Congress to prevent 'Medicaid cliff' | The Hill: Healthcare Policy

Welcome to Friday's Overnight Health Care. The government has no firm explanation for more than 140 UFOs that have been officially reported. They're not saying it's aliens, but they're also not NOT saying it's aliens. If you have any tips,...