By Thomas Moore, Health And Science Correspondent
As a Spanish nurse becomes the first person outside West Africa to be infected with ebola, here we answer some of your questions.
Now the virus is in Europe, should I panic?
No. The infection of the Spanish nurse is almost certainly a one-off.
Health workers have to go through a strict de-robing procedure to prevent the virus being transferred from their protective gowns onto their skin.
If clothes are removed in the wrong order, if any shortcut is taken on handwashing, or if any sweat is wiped away from the eyes, there can be contamination.
It does not mean the virus is on the loose in Europe. The nurse's contacts have been traced and those deemed to be at high risk have been quarantined as a precaution.
The general population in the UK - or Spain, for that matter - is at no greater risk of ebola today than it was a week ago.
Why bring infected health workers back from Africa at all?
British doctors and nurses are already treating ebola patients in West Africa.
Many more will be on their way within weeks, answering the humanitarian call to help countries that have been overwhelmed by the disease.
So far just one - Will Pooley - has been infected and brought back for treatment at London's Royal Free Hospital.
He would not have been able to get the best medical care in Sierra Leone, so the Government repatriated him with strict - and successful - quarantine controls.
But the International Development Secretary Justine Greening has acknowledged on Sky News there is a risk in transferring patients and a hospital is being built with UK money in Sierra Leone.
It will have 12 beds set aside for infected healthcare workers.
What about travellers - shouldn't we screen them?
Public Health England says there is no reason to check arriving air passengers for ebola symptoms. That's in line with advice from the World Health Organisation.
Firstly, it would duplicate the screening of people departing on flights from the affected countries in West Africa.
Secondly, British Airways has suspended direct flights between the UK and Sierra Leone and Liberia.
So passengers from the region would have to change planes in Paris, Brussels, or many other capitals.
Tens of thousands of passengers would have to be checked every day, causing long delays.
Thirdly, temperature scans only detect people with symptoms.
A Liberian passenger treated in hospital in the US was healthy when he travelled and only developed symptoms several days later. Checks on arrival wouldn't have picked him up.
He has now died in a Dallas hospital.
So is the NHS prepared?
GPs have been sent a symptom checklist by Public Health England.
Anybody with a fever, who has recently returned from one of the affected countries in West Africa, will be rapidly risk-assessed.
If there is a high chance that their symptoms are due to ebola - rather than malaria or any other tropical disease - they will be quarantined at the Royal Free Hospital in London.
What if we get lots of ebola cases?
The specialist unit at the Royal Free has two beds.
But other NHS hospitals are on standby.
The Royal Liverpool, Royal Victoria in Newcastle and Royal Hallamshire in Sheffield are next in line to receive patients.
And any hospital with an infectious diseases unit could be adapted with quarantine canopies around beds to safely care for patients.