UKHSA Health Protection Briefing Note: 2025/010 Case of Lassa Fever with Travel to UK

Lassa fever is a viral haemorrhagic fever and classified as a high consequence infectious disease (HCID) in the UK.

On 05 March 2025, the UK was informed by the IHR National Focal Point of Nigeria of a case of Lassa fever who had travelled to the UK while symptomatic. The case came into contact with a number of individuals while symptomatic in the UK, and UKHSA is conducting contact tracing in a number of locations across
England.

Clinicians are reminded that they should be alert to the possibility of Lassa fever in unwell patients presenting where there is a history of travel to Nigeria, or to other countries where there is a risk of Lassa fever, or a link to a suspected or confirmed case, within 21 days before onset of illness.

Where appropriate, clinicians should follow the ACDP guidance for risk assessment and management of viral haemorrhagic fevers to safely assess and test such patients.

NHS infection services should discuss suspected cases with the Imported Fever Service (IFS) to discuss urgent testing. Confirmed cases will be managed via the HCID network. Suspected cases should also be notified to the local health protection team.

Read more in the UKHSA official briefing note.