A Scottish nurse diagnosed with
"Safety measures are working well -- and the risk to the public is extremely low," Prime Minister David Cameron posted on Twitter before chairing an emergency meeting on the Ebola case.
Healthcare worker Pauline Cafferkey, who had been treating Ebola patients in Sierra Leone, was diagnosed with the disease hours after arriving home to Glasgow on Sunday on flights via Casablanca and London.
Scotland's first minister, Nicola Sturgeon, said at a news conference shortly after the meeting with Cameron that Cafferkey was "doing as well as could be expected in the circumstances," but refused to elaborate.
Public health officials were trying to contact any passengers who were on the planes with Cafferkey, but stressed that the risk of transmission was "extremely low."
Cafferkey had been volunteering for Save the Children in Sierra Leone for the last month, working on the front line in the fight against Ebola. The virus has infected more than 20,000 people and claimed about 7,880 lives, most of them in West Africa, according to the latest estimates from the World Health Organization.
She landed in Scotland about 11:30 p.m. Sunday and was placed in isolation in Glasgow's Gartnavel Hospital at 7:50 a.m. Monday after feeling unwell, a statement from the Scottish government said.
Early Tuesday, a convoy of emergency vehicles brought her to a Royal Air Force Hercules plane, which took her to London. Upon arrival, she was taken by ambulance to a high-level isolation unit at the Royal Free Hospital.
Images broadcast on television showed the patient inside a quarantine tent and surrounded by healthcare workers wearing protective clothing.
Cafferkey is the second Briton to be infected with Ebola but the first to be diagnosed on British soil.
The first patient was William Pooley, 29, a nurse who was volunteering in Sierra Leone when he contracted Ebola in August. He was also treated at the Royal Free Hospital and has since returned to the West African nation to continue treating patients.
Cafferkey, who has 16 years of experience as a nurse, had been working at a treatment center in Kerry Town, Sierra Leone, and recently wrote a journal for the Scotsman newspaper in which she described her harrowing experiences watching whole families being wiped out in the infectious "Red Zone."
She also spoke to the BBC shortly before her trip and said she was prepared for the risks but also excited to be able to help.
"For me it was kind of a natural thing; I couldn't think of any reason why not to go," she said.
"You've got to have a certain element of fear. You don't want to go into this being complacent."
She was among a group of up to 50 healthcare workers from Britain's National Health Service who returned from Sierra Leone over the weekend.
A second patient who recently returned from West Africa was also being tested for Ebola, but is considered at "low probability" of having the disease, officials said.