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 country has died.
Public Health England (PHE) said three British people who had stayed in Sierra Leone and had close contact with the Dutch pair had been repatriated to be medically assessed and treated, if required. The agency has also got in touch with 15 other British nationals who had contact with the pair to monitor them.
Dr Jake Dunning, the 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, the symptoms of which are similar to Ebola. Starting as a fever with aches and pains, Lassa can progress to headache, vomiting and diarrhoea. There can also be bleeding from the mouth and nose in severe cases, according to the World Health Organization.
Like Ebola, Lassa fever can be spread through contact with the bodily fluids of those infected. It can also be contracted from 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.