Because it's not a quarantine. Or really even a restriction on her movements. The order is available here. The order only requires Hickox to do three things:
1. Participate in and cooperate with "Direct Active Monitoring," as that term is defined by the United States Centers for Disease Control in its October 29, 2014 [guidance];
2. Coordinate her travel with public health authorities to ensure uninterrupted Direct Active Monitoring; and
3. Immediately notify public health authorities and follow their directions if any symptom appears.
This is a loss for quarantine advocates (and a win for Hickox), because these rules are consistent with (and do not go beyond) the CDC guidance for people in Hickox's risk class, and Hickox had already agreed to abide by the CDC rules.
Thank you for the clarification.
It’s a win for the anti-quarantine crowd so far...
If even one of the hundreds of returnees like her passes on the virus then a strict quarantine will be demanded by the public.
That would be bad as West Africa is a huge test lab for Ebola medicines and treatments. America should be participating there and her actions risk making it very difficult for us to do so.
Voluntary self-directed ‘quarantines’ would no longer be an option. Ironically just the opposite of the outcome wanted by those she is trying to please.