Federal officials/agencies should not be allowed to accept any money from the companies they regulate including working for those companies ever.
As a condition of employment they must disclose any conflicts of interest to the public. Heads of FDA, CDC, FEMA, FBI, CIA ect. Should be voted for by the citizens.
Violating this should be mandatory imprisonment not a fine. Also they must sign and affidavit acknowledging that they have no conflicts of interest.
All current officials will need to sign this affidavit or resign from their position.