Is North Carolina's Ebola Quarantine Justified?

I'm puzzled by the announcement that asymptomatic individuals returning to the Charlotte area from Liberia are being quarantined for a period of 21 days because of concern they may be incubating Ebola.

Several important questions that I think need to be answered include:

  • Is this a "voluntary" quarantine or is it mandated? What is the penalty for breaking it?
  • Who is the governing authority? Mecklenberg County or the state of North Carolina?
  • Where will these individuals be confined to? Their homes? A facility? 
  • Since Ebola is not casually transmitted what is the evidence that such a quarantine would be effective?
  • If this is to be taken as a precedent are all CDC officers deployed to West Africa to be quarantined upon return as well? 
  • It's OK to fly, but not to freely move about Mecklenberg County?
  • Why was this action never undertaken with travelers to prior Ebola outbreaks, Lassa Fever outbreaks, or to the Middle East (where the more contagious MERS circulates)?

Authorities say this quarantine order is being issued "out of an abundance of caution" but it does not excuse taking actions without an actual risk-based justification. To me, this quarantine delivers a mixed message to a public desperate for clarity on the actual transmission risk of Ebola.