Operational mpox (monkeypox) HCID case definition
This guidance is for healthcare workers and describes the operational case definitions to determine a suspected or confirmed case of Clade I mpox (monkeypox).
Operational case definition
All laboratory confirmed mpox (monkeypox) Clade I cases should be managed as a high consequence infectious disease (HCID).
Operational management as HCID
Patients with confirmed or clinically suspected mpox but clade not yet known should be managed as a HCID mpox case whilst further information is pending, if either (or both):
- there is a travel history to the Democratic Republic of the Congo (DRC) or specified countries where there may be a risk of Clade I exposure, or a link to a suspected case from those countries (listed below), within 21 days of symptom onset
Or:
- there is an epidemiological link to a case of Clade I mpox within 21 days of symptom onset
Cases when mpox is not considered an HCID
Mpox is not considered an HCID in the following circumstances:
- a case has a laboratory confirmed Clade II monkeypox virus (MPXV) infection
Or:
- a confirmed or clinically suspected mpox case of an unknown clade and none of the epidemiological characteristics listed above in Operational management as HCID apply
Countries where there may be a risk of Clade I exposure
Given the rapid spread of Clade I in the African Region, please check the UKHSA mpox pages regularly for any updates to the countries included.
The countries reporting laboratory-confirmed Clade I mpox (historic or current) include:
- DRC
- Republic of the Congo
- Central African Republic
- Burundi
- Rwanda
- Uganda
- Kenya
- Cameroon
- Gabon
The countries where there may be a risk of Clade I mpox exposure (base on sharing a border with the DRC) currently include:
- Angola
- South Sudan
- Tanzania
- Zambia
Figure 1. African Region countries reporting laboratory confirmed Clade I mpox or where there may be a risk of Clade I mpox exposure
Management of cases
Clinicians should be alert to the possibility of Clade I mpox if there is a link to the specified countries in the African region (as listed), and those treating patients with suspected mpox who may meet the operational definition of an HCID (as outlined above) should discuss with the Imported Fever Service (0844 778 8990) to expedite testing. Patients with severe disease should also be discussed with the Imported Fever Service.
Confirmed or probable Clade I cases should be managed as a HCID requiring transmission-based precautions and enhanced personal protective equipment (PPE) as outlined in the National Infection Prevention and Control Manual.