A patient who recently arrived in England from Africa has been diagnosed with monkeypox, health officials said.
The individual has a recent travel history from Nigeria, which is where they are believed to have contracted the infection, before traveling to Britain.
They are now receiving care at the expert infectious disease unit at the Guy's and St. Thomas' NHS Foundation Trust in London.
Experts from the U.K. Health Security Agency (UKHSA) are monitoring the case and working closely with National Health Service (NHS) colleagues to contact people who might have been in close contact with the individual.
Colin Brown, director of clinical and emerging infections at the UKHSA, said: "It is important to emphasize that monkeypox does not spread easily between people and the overall risk to the general public is very low.
"We are working with NHS England and NHS Improvement (NHSEI) to contact the individuals who have had close contact with the case prior to confirmation of their infection, to assess them as necessary and provide advice.
"The UKHSA 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."
The first United Kingdom case of monkeypox was recorded in September 2018. The individual was also believed to have contracted the infection in Nigeria.
Initial symptoms include fever, headache, aching muscles, backache, swollen lymph nodes, chills and exhaustion.
A rash can also develop, usually starting on the face before spreading to other parts of the body. It eventually forms a scab that falls off.
PHE said monkeypox does not spread easily and most patients recover within a few weeks, but it can cause severe illness in some people.
Nicholas Price, director of the NHSEI high consequence infection diseases (airborne) network and consultant in infectious diseases at Guy's and St. Thomas', said: "The patient is being treated in our specialist isolation unit at St. Thomas' Hospital by expert clinical staff with strict infection prevention procedures.
"This is a good example of the way that the high consequence infectious diseases national network and UKHSA work closely together in responding swiftly and effectively to these sporadic cases."/DPA