Three British nationals have been brought back to the UK from Sierra Leone for medical assessment after coming into close contact with two people diagnosed with Lassa fever.
One of the two Dutch nationals who contracted the virus, whose symptoms are similar to Ebola, while working in the West African nation has died.
Public Health England (PHE) said three British people who had stayed in Sierra Leone and had close contact with them have been repatriated by the UK Government to be medically assessed and treated, if required.
The agency has also contacted another 15 British nationals who had contact with the Dutch Lassa fever cases to monitor them.
Dr Jake Dunning, head of emerging infections and zoonoses at PHE, said: "It is important to emphasise that Lassa fever does not spread easily between people and the overall risk to the public is very low.
"There are no confirmed cases of Lassa fever in the UK.
"PHE is monitoring those who have had close contact with the foreign national to assess them as necessary and provide advice.
"PHE and the NHS have well established and robust infection control procedures for dealing with cases of imported infectious disease and these will be strictly followed."
There is no approved vaccine for Lassa fever, whose symptoms are similar to Ebola.
After starting as a fever with aches and pains, it can progress to headache, vomiting and diarrhoea.
According to the World Health Organisation, severe cases can cause victims to bleed from the mouth and nose.
Like Ebola, Lassa fever can be spread through contact with the bodily fluids of sick people.
Humans can also contract it from eating food that has been tainted by the urine or faeces of rodents.
PHE said most people with Lassa fever make a full recovery, although severe illness can occur.