Purpose

1. In light of the UKHSA principles paper, a risk stratified clinical approach has been developed to ensure that confirmed cases of monkeypox receive appropriate care, while also managing transmission risk. This approach is being further modified to take account of the derogation of the current specific monkeypox clade (clade IIb with lineage B.1) AND (as of December 2022) cases in clade II non-B.1 lineage (i.e those associated with travel to West Africa) as a High Consequence Infectious Disease (HCID).

2. A UK wide clinical policy statement has also now been published guiding access to tecovirimat in individuals hospitalised due to monkeypox infection.

3. This document will be updated as further information becomes available.

4. In addition, the World Health Organisation has announced that monkeypox is to be renamed mpox to help tackle discrimination and stigma.

Background

5. Mpox primarily occurs in Central and West Africa. Symptoms of mpox begin 5-21 days (average 6-16 days) after exposure with initial clinical presentation of fever, malaise, lymphadenopathy and headache. Within 1 to 5 days after the appearance of fever, a rash develops, often beginning on the face or genital area then spreading to other parts of the body. The rash changes and goes through different stages before finally forming a scab which later falls off. The illness is usually mild and most of those infected will recover within a few weeks without treatment. The mortality from mpox is low (1% in Africa) with those who are pregnant, children and immunocompromised hosts being at highest risk.

6. Admission to highly specialist ‘containment’ facilities within the (Airborne) HCID Network would normally be mandated for all cases confirmed by UK Health Security Agency (UKHSA) specialised laboratories. This is no longer the case following the derogation of the specific current outbreak clade and, as of December 2022, cases in clade II non-B.1 lineage (i.e. those associated with travel to West Africa) as HCIDs.

7. First diagnosed in the UK in 2018, mpox had been a rare and sporadic imported infection. The NHS England HCID Network successfully managed all seven cases from 2018-21.

8. Since then, there has been a large outbreak of mpox in several European countries, including the UK, and further afield globally. While the UK’s first case in May 2022 involved travel to Nigeria, all subsequent cases have none of the typical exposure risks and represent chains of transmission with the UK population. The majority of cases in the 2022 clade IIb outbreak in the UK have so far been detected in gay, bisexual and other men who have sex with men (GBMSM) in London.

9. The UK clinical and public health response to mpox was initially based on the HCID system. This was highly precautionary and designed for complete containment around single cases or small clusters. It was also designed prior to the confirmed availability of vaccine and treatment. UKHSA confirmed in 2022 that community transmission of clade IIb virus is occurring in the UK with multiple generations of spread. Illness has been non-severe in the majority, with most cases not requiring inpatient care.

10. In June 2022, the Advisory Committee on Dangerous Pathogens (ACDP) recommended that the strain of mpox (clade IIb B.1) in community transmission at that time within the UK should no longer be classified as an HCID. In reaching its recommendation, ACDP considered evidence showing associated with lower mortality and less serious illness than previously observed with mpox cases in the UK and elsewhere.

11. The four nations public health agencies discussed this advice and agreed with the view of ACDP, and HCID status was removed for mpox caused by clade IIb B.1 virus.

12. Following the receipt of further advice, the ACDP has subsequently decided that all cases in clade II (including those with non-B.1 lineage and which are associated with travel to West Africa) no longer need to be managed as HCIDs. The is because of the relatively benign clinical phenotype of the currently circulating lineage B1 within clade IIb, along with firm evidence of effectiveness of available vaccines, access to rapid diagnostic testing, heightened clinical awareness of this infection, and access to safe therapies with experimental evidence of efficacy. Any cases associated with clade I (previously known as the Central Africa clade) MUST still be managed as HCIDs. At present, there have been no confirmed cases in this clade in the UK.

Risk stratification

13. There is a need to balance the requirement to contain the spread of mpox in the community and within healthcare settings, while acknowledging that the NHS is adopting a more proportionate approach to admissions, based upon a patient-level assessment and stratification of risk.

14. The following groups of individuals have underlying risk factors for severe disease and may require hospitalisation. Cases involving the below MUST be discussed with your local Specialist Regional Infectious Disease Centre (SRIDC) and can be discussed with one of the HCID Centres:

• Pregnant patients
• Immunocompromised individuals
• Children (16 years or under).

15. Caution should be exercised in treating pregnant patients with tecovirimat for mpox infection. Please see the policy for guidance. Clinicians may wish to seek further discussion with an HCID Centre in such situations.

16. Clinicians should assess patients and make a judgement as to whether they require admission. Where a clinician feels admission is needed, they should use their usual route for securing access to infectious disease advice and provision and to determine whether hospitalisation is needed.

17. Experience of treating over 60 inpatients in this outbreak clade has demonstrated that individuals have needed hospitalisation for:

• Severe, refractory pain, commonly proctitis
• Eye disease
• Severe secondary bacterial infections or co-infection with STIs
• Multiple lesions or those that require surgical intervention
• Lesions associated with complications due to pain or swelling, e.g. constipation, urinary retention or inability to swallow
• Rarely, encephalitis and pneumonitis.

18. Any patient who has mild disease should self-isolate at home until recovery. This covers the majority of cases that we have seen during this outbreak. Their responsible clinician should advise the patient to get in contact with them if their condition deteriorates. Clinicians are actively encouraged to support recruitment of patients with laboratory confirmed mpox infection and with active skin or mucosal lesions, but who do not require hospital admission, to the PLATINUM trial.

19. Patients requiring hospitalisation must, at a minimum, be treated in a respiratory isolation room by staff using the recommended PPE, although this does not necessarily need to be in an infectious disease unit. A respiratory isolation room is a ventilated single occupancy room with an en suite bathroom. The ventilation options are a negative pressure room, or a positive pressure ventilated lobby (PPVL) patient room connected to an en suite bathroom with extract ventilation and with a positive pressure ventilated lobby.

20. Clinicians should use their usual route for securing access to infectious disease advice and provision if the patient requires inpatient care.

21. Where required, infection specialists in SRIDCs (see Appendix A) may obtain further advice from their nearest (airborne) HCID centre.

22. UKHSA, with funding from DHSC, has secured a supply of the anti-viral, tecovirimat, and a UK wide clinical policy statement covering its use in patients who are hospitalised due to a mpox infection has been published following approval from the Chief Medical Officer. To date, due to the complexity of treatment needs, the majority of the use of tecovirimat has been in adults in SRIDCs. Stocks of the oral formulation are therefore being held in these locations and can be couriered, on an exceptional basis, to other providers. Use of tecovirimat in children under the age of 16 must be discussed on an MDT with one of the paediatric HCID Centres.

23. All inpatient activity should be coded using the ICD10 code B04 so that a retrospective analysis of admissions can be undertaken.

Management of suspected or laboratory-confirmed positive clade I cases

24. Mpox cases in clade I (previously known as the Central Africa clade) MUST continue to be managed as HCIDs (see Appendix A), as the associated morbidity and mortality may be greater. Any cases with a reported travel history to Central Africa in the 21 days before symptom onset should be discussed with a local infection consultant (microbiology, virology or infectious diseases) who should discuss the case with the Imported Fever Service (who will be able to confirm whether or not the case is an HCID and alert relevant people). Cases with a confirmed travel history to Central Africa should be treated as HCIDs until the case has been sequenced and the clade has been identified. The distribution of clade I may change over time and there have been cases of clade I ex-Ghana. The relevant local infection prevention and control team should be informed of any suspect cases admitted. Where there is no local infection consultant available, the UKHSA Imported Fever Service may be contacted directly – enquiries process and contact information is available via GOV.UK – Imported fever service (IFS)

Appendix A – Specialist infectious disease provision in England

The following trusts in England form the Specialist Regional Infectious Disease (with HCID Centres indicated with an *)

• Alder Hey Children’s NHS Foundation Trust (children*)
• Barts Health NHS Trust (London) (adults and children)
• Brighton and Sussex University Hospitals NHS Trust (adults)
• Cambridge University Hospitals NHS Foundation Trust (adults)
• Guy’s & St Thomas’ NHS Foundation Trust (adults* and children*)
• Hull University Teaching Hospitals NHS Trust (adults)
• Imperial College Healthcare NHS Trust, London (adults and children*)
• Leeds Teaching Hospitals NHS Trust (adults)
• Liverpool University Hospitals NHS Foundation Trust (adults*)
• London North West University Healthcare NHS Trust (Northwick Park Hospital) (adults)
• Manchester University NHS Foundation Trust (adults and children)
• Nottingham University Hospitals NHS Trust (adults)
• North Bristol NHS Trust (adults in conjunction with University Hospitals Bristol and Weston NHS Foundation Trust))
• Oxford University Hospitals NHS Foundation Trust (adults and children)
• Royal Devon and Exeter NHS Foundation Trust (adults)
• Royal Free London NHS Foundation Trust (adults*)
• Sheffield Children’s NHS Foundation Trust (children)
• Sheffield Teaching Hospitals NHS Foundation Trust (adults*)
• South Tees Hospitals NHS Foundation Trust (adults)
• Southampton University Hospital NHS Foundation Trust (children)
• St George’s University Hospitals NHS Foundation Trust, London (adults and children)
• The Newcastle upon Tyne Hospitals NHS Foundation Trust (adults* and children*)
• University College London Hospitals NHS Foundation Trust (adults)
• University Hospitals Birmingham NHS Foundation Trust (adults, children in-reach to Birmingham Women’s & Children’s Hospital NHS Foundation Trust)
• University Hospitals Bristol and Weston NHS Foundation Trust (adults in conjunction with North Bristol NHS Trust, children)
• University Hospitals of Leicester NHS Trust (adults)
• University Hospitals of North Midlands NHS Trust (Stoke) (adults)