Medical authorities in the Netherlands and the UK have said dozens of people are under observation for Lassa fever following the death of a doctor who contracted the virus in Sierra Leone.
The unnamed Dutch doctor contracted the Ebola-like virus while working at Masanga Hospital in the country's Tonkolili district and died over the weekend after being brought home to the Netherlands for treatment.
He was described as a medical professional who had admirable "knowledge, capacity and passion to improve access to surgical care" in a statement from his employer, Capacare International.
It added: "The way he was able to provide his patients the best possible treatment and his students thoughtful guidance never stopped to impress us."
Meanwhile, the Netherlands National Institute for Public Health and the Environment (RIVM) confirmed to Euronews that a total of seven people had been repatriated to the Netherlands, including the unnamed doctor, and another Dutch doctor who contracted the virus.
It added that a further 20 people were under observation.
Public Health England (PHE) also confirmed to Euronews that it had repatriated three British nationals who had been in close contact with the two Dutch doctors, and had contacted 15 more people for monitoring purposes.
It stressed that there were no confirmed cases of Lassa fever in the UK and the risk to the local population was "very low".
Jake Dunning, Head of Emerging Infections and Zoonoses at PHE, said: "There are no confirmed cases of Lassa Fever in the UK. Public Health England is monitoring those who have had close contact with the foreign national to assess them as necessary and provide advice.
"PHE and the [National Health Service] have well established and robust infection control procedures for dealing with cases of imported infectious disease and these will be strictly followed."
According to the World Health Organisation (WHO), Lassa fever is "an acute viral haemorrhagic illness" which humans can contract if exposed to the excrement of infected Mastomys rats.
Fatality rate is around 1% and is rarely symptomatic; however, it can start with a fever and gradual weakness and deteriorate into seizures, shock and a coma, if it is.