Ebola is only contagious once symptoms appear. Also, Ebola is not spread through aerosols, but by direct contact with infected fluids, including droplets. So, if this woman vomited or had diarrhea and droplets got onto people, there could be a problem. Otherwise, not.
Personally, I think it is silly to announce every potential case being tested for Ebola. There are many other diseases in Africa, including other hemorrhagic fevers. If a case pops positive, *then* I want to see the results.
Can you provide a link to the source on this? I've searched the CDC and other Ebola sites and none of them state this specifically.