This guidance is for healthcare professionals on when to suspect mpox, the disease caused by any clade of the virus called MPXV, and how to decide if a suspected case needs to be managed as a High Consequence Infectious Disease (HCID). Clade II mpox has been circulating in the UK and globally since 2022 predominantly in gay, bisexual or other men who have sex with men, but remains uncommon. SinceIt 2022, it is no longer classified as aan high consequence infectious disease (HCID)..

Clade I mpox is currently classified as an HCID. It includes clade Ia, present in central Africa, and clade Ib, whichcurrently incausing 2024 to 2025 has caused an outbreak in multiple countries (see the affected country list).

Consider Cladethe Ipossibility of mpox waswhen classifiedpatients aswith anexposure risk and which fit the clinical description in the section on When to suspect mpox. When assessing patients for mpox, always consider the possibility of HCID untiland earlytake 2025.a Followingtravel advicehistory. fromIf the Advisorypatient Committeefits onthe DangerousHCID Pathogenscase (ACDP),definition, itthey isshould nobe longermanaged classified as anpotential HCID and discussed with local infection team, who may refer to the Imported Fever Service.

ClinicalWhen assessmentto suspect mpox

Consider mpox where a case presents with:

1. a prodrome (fever, chills, headache, exhaustion, myalgia, arthralgia, backache, lymphadenopathy), inand anwhere individualthere withis known prior contact with a confirmed or suspected case of mpox in the 21 days before symptom onset

Or:

2. an mpox-compatible rash anywhere on the skin (face, limbs, extremities, torso), mucosae (including oral, genital, anal), or symptoms of proctitis, and at least one of the following in the 21 days before symptom onset:

• recent new sexual partner
• contact with known or suspected case of mpox
• a travel history to a country where mpox is currently common - this does not include people transiting through the affected country where they do not leave the airport
• link to an infected animal or meat

Or:

3.If anthe mpox-compatible rash anywhereis onhighly theclinically skinsuggestive (face,of limbs,mpox, extremities,but torso),you mucosaecannot (includingidentify oral,a genital,risk anal),factor, ordiscuss symptomswith oflocal proctitis,infection whereservices therewhether isto noconsider riskmpox factortesting andalongside nothe alternativemore common differential diagnosisdiagnosis.

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Actionsas forHCID aif casethey ofmeet mpox

Forone allor suspectedmore mpoxof cases

Forthe patientsfollowing beingcriteria:

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• has 8990a forrelevant clinicalzoonotic advice,link, forincluding examplecontact inwith patientsa whowild areor severelycaptive immunocompromisedmammal orthat pregnant,is paediatrican patients,African ornative patientsspecies from(this aincludes highcontact riskwith settingderived suchproducts, asfor sharedexample, accommodation.
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Test

Actions for MPXV,for thea causativesuspected agentcase of mpox

For usingall ansuspected appropriatempox testingcases

Patients pathway.identified Seeas also Mpoxsuspected diagnosticmpox testingcases guidance.

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For confirmed cases

A confirmedmeeting casethe isHCID definedmpox ascase adefinition

The personmanaging withclinician ashould laboratory-confirmedcontact mpoxtheir infectionrelevant (MPXV PCR positive).local Confirmedinfection casesteam should(infectious bediseases, notifiedmicrobiology, urgentlyor tovirology). theThe healthlocal protectioninfection team (HPT).should Furtherthen guidancediscuss onwith contact tracingthe IFS, (0844 guidance778 for8990) thosewho isolatingwill atreview home,risk andassessment de-isolation and dischargeadvise ison available.the  

Mostnext patientssteps whofor haveinvestigation mildand management symptomsincluding andthe whoneed arefor ableadmission. toIf self-isolatea candecision beis managedmade asto outpatientstest, withinformation follow-upon viadiagnostic atesting virtualfor wardmpox oris similar,available. byThe localmanaging infectionclinician servicesshould orcontact sexualthe local health services.protection team.

For severe cases (suspectedthat ordo confirmed)not meet the HCID mpox case definition

TheTest managingfor MPXV, clinicianthe shouldcausative contactagent theirof localmpox infection(using teamdesignated (infectioustesting diseases,pathway). microbiology,See virology).also Mpox Ifdiagnostic needed,testing theguidance.

Undertake localtests infectionto teamrule canout discussalternative withdiagnoses theif Importedclinically Feverappropriate Serviceand (0844if 778not 8990)done already.

If patient requires admission for adviceclinical onreasons, IPC measures theshould nextbe stepsundertaken as per the NHS guidance on IPC measures for investigationclinically suspected and management,confirmed includingcases theof needmpox forin admissionhealthcare andsettings and treatment.the national IPC manual.

TheIf NHSpatient indoes allnot 4require nationsadmission willfor continueclinical toreasons: drawadvise self-isolation at home (based on assessment by the expertiseclinician ofand HCIDfollowing UKHSA guidance). unitsIf inthe patient cannot self-isolate at home, the assessmentpatient andshould managementbe ofadmitted casespending requiringtest admissionresult, towith IPC measures hospital.undertaken Thisas reflectsper thethe NHS potentialguidance on IPC measures for severeclinically diseasesuspected dueand toconfirmed anycases cladeof mpox in vulnerablehealthcare groups.settings and Inthe national IPC manual.

Case addition,definitions thereonce maytest beresults specificare infectionavailable

Highly controlprobable riskscase

A inhighly patientsprobable case is defined as a person with extensivean diseaseorthopox virus PCR positive result where inputmpox fromremains the HCIDmost networklikely maydiagnosis.

Confirmed becase

A helpful.confirmed case is defined as a person with a laboratory-confirmed mpox infection (MPXV PCR positive).

Further information

Additional mpox resources are available on GOV.UK, including guidance on vaccination.