Updated with changes to contacts eligible for post exposure vaccination following decision in April 2025 that all clades of mpox no longer met the criteria for a high consequence infectious disease (HCID).

Updated epidemiology following clade I cases in UK and clarification of advice in the event of a failed intradermal administration.

Major update to include information on recent increase in clade I MPXV, new information on vaccine effectiveness and advice on outbreak response.

Updated to include information on prioritising second doses.

Added the option to use the deltoid area for intradermal administration of the vaccine.

Corrected minor error in table.

Updated to include information on intradermal vaccination and further clarification on the prioritisation during supply constraints.

Revised to include advice on deferral of vaccination in recent cases, information on using IM administration, and change to definition of vulnerable children.

Revised to include information on the new smallpox (MVA) vaccine and the response to cases of monkeypox.

First published.