Worryingly, I find myself frequently in agreement with you on here, K. I listened to the usual woodentops on Radio 4 this morning telling us how well 'the systems' had worked etc, etc. But no one asked the question you posed. We now are spending vast sums tracking down anyone who was near this modern day Edith Cavell as she apparently flew unconcerned around half the globe.
I was an aid worker in Sierra Leone in 99,2000 hard country. Lots of horrible diseases a lad with us died of Lassa Fever, like Ebola but less virulent. Can only admire the workers who go there, hopefully she will pull through.
The problem here is the health people making the decisions seem quite pleased with themselves over their prevention plans and advice which are clearly inadequate.
Now some things should be obvious to them but clearly are not...
Taking a temperature is NOT a screening test for Ebola....
People who travel after working in health care treating Ebola patients are clearly a much higher risk than the average traveller from the area therefore must undergo more rigorous screening and assessment.
It should have been obvious that this worker would have been at an increased risk by just looking at the other cases involving health carers yet she was allowed to travel on one plane, catch another and then make her way to her home without any adequate monitoring.