Nearly 100 people have been tested for Ebola in hospitals across the UK so far this year, according to Public Health England (PHE).
The deadly virus has claimed more than 5,000 lives across west Africa.
In a Freedom of Information response to the Press Association, PHE said the ages of patients tested between January 21 and November 9 ranged from "under five" to 75 years old. Words: PA
Most of the people tested for Ebola had visited west Africa, PHE added.
A PHE spokesman said one person in England had tested positive for the disease and the case was "in the public domain".
Nurse William Pooley, 29, contracted Ebola while volunteering in Sierra Leone in August before getting the all-clear following treatment at the Royal Free Hospital in London.
He returned to Sierra Leone last month to continue treating patients in an Ebola isolation unit run by UK medical staff.
The PHE refused to provide a breakdown of the number of men and women tested, the locations of hospitals where tests were carried out or the African countries visited by the patients.
A spokesman said: "If PHE disclosed all the information requested we would be releasing enough information to identify the individuals tested due to deductive disclosure. PHE has a duty to ensure that this does not occur."
Meanwhile, a woman with a history of travel to west Africa tested negative for Ebola at St George's Hospital in Tooting, south London, earlier this month after complaining of a fever.
David Mabey, professor of communicable diseases at the London School of Hygiene and Tropical Medicine, warned the UK may see its second case of Ebola as more NHS staff fly out to west Africa to help tackle the crisis.
"To get infected you have got to be in close contact with a patient," he said.
"More people are going out there, about 30 NHS staff have just gone, so we may get a case or two but they have been very well trained by the army."
Prof Mabey said the number of Ebola tests carried out in hospitals in England this year "came as no surprise.
"Lots of people come and go between here and west Africa," he said.
"Some will get a fever, like the patient recently admitted to St George's Hospital. There will be cases of malaria. Obviously anyone coming back with a fever has to be tested."
Asked whether the Government's decision to introduce screening for Ebola at airports had been effective, he replied: "No because nobody has been picked up so it's obviously not made any difference."
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