Update. "US #NIH reverses conference travel ban for scientists"
https://www.reuters.com/business/healthcare-pharmaceuticals/us-nih-scientists-barred-attending-conferences-their-own-time-dime-2025-04-10/
"Researchers at the US National Institutes of Health had been told they cannot attend scientific conferences and meetings without official permission, even if they paid their own way and went during time off… After Reuters reported the travel restriction policy earlier on Thursday, an #HHS spokesperson said, 'Effective April 10, official travel may resume following established approval processes within each Institute and Center.'"
Neither the original travel restrictions nor the recent reversal have been put in writing.