Lassa Fever Cases Confirmed in East of England

The UK Health Security Agency (UKHSA) press office today announced two people had been diagnosed with Lassa fever in the East of England. Cases of Lassa fever are rare in the UK, and it does not spread easily between people.

Dr. Susan Hopkins, Chief Medical Advisor at UKHSA, said in a press statement, "We can confirm that two cases of Lassa fever have been identified in England, and a further probable case is under investigation."

"The cases are within the same family and are linked to recent travel to West Africa."

"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."

Lassa fever is an acute viral hemorrhagic illness. People usually become infected with the Lassa virus through exposure to food or household items contaminated with urine or feces of infected rats, present in several West African countries where the disease is endemic.

The virus can also be spread through infected bodily fluids.

Before these cases, there have been eight cases of Lassa fever imported to the UK since 1980. The last cases occurred in 2009, and there was no evidence of onward transmission from any of these cases, says the UKHSA.

Currently, there are no Lassa fever vaccines commercial available.

However, in October 2021, Pennsylvania-based INOVIO announced its Phase 1B clinical trial for INO-4500, its DNA vaccine candidate for Lassa fever, had completed full enrollment of 220 participants. This trial is ongoing at the Noguchi Memorial Institute for Medical Research in Ghana.

And INO-4500 is the first vaccine clinical trial for Lassa fever conducted in West Africa.