Two people in the UK have been diagnosed with Lassa fever, a virus which is endemic in several West African nations.
The UK Health Security Agency (UKHSA) have said that those infected are members of a family that recently returned from West Africa and live in the East of England.
Additionally, a third member of the family is under investigation to see if they have the virus.
Lassa fever is usually caught from exposure to food or household items contaminated with the urine or faeces of infected rats.
It can also be transmitted through contact with infected bodily fluids.
Symptoms can include vaginal bleeding and deafness.
This is the first time the disease has been found in the UK since 2009 - and there have only been eight previous cases in the country.
Dr Susan Hopkins, chief medical adviser at UKHSA, said: "Cases of Lassa fever are rare in the UK and it does not spread easily between people.
"The overall risk to the public is very low.
"We are contacting the individuals who have had close contact with the cases prior to confirmation of their infection, to provide appropriate assessment, support and advice."
As reported by Sky News, only 1% of people infected with the Lassa virus die, according to the World Health Organisation.
The news outlet described Lassa virus as an "Ebola-like virus".
About 80% show no symptoms, while others experience a fever with aches and pains that can progress to headaches, vomiting and diarrhoea.
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