Mpox (Monkeypox)
Quick clinical summary
Mpox is caused by the monkeypox virus (MPXV), an orthopoxvirus related to smallpox. Incubation is typically 5-21 days.
Presentation ranges from a systemic prodrome (fever, myalgia, headache, prominent lymphadenopathy) followed 1-5 days later by a vesiculopustular rash, to atypical localized disease (for example, a single genital or perianal lesion, proctitis, or oropharyngeal lesions).
Transmission requires close contact (skin-to-skin or mucosal contact), prolonged face-to-face respiratory exposure (respiratory droplets), or contaminated fomites. Most cases are mild and managed supportively, but early isolation, appropriate sampling and rapid public-health liaison are essential (UKHSA).
When to suspect mpox Consider mpox when any of the following apply:
- An mpox-compatible rash (even a single ulcerative lesion) or an unexplained vesicular/pustular eruption, particularly involving the face, palms/soles, genital or perianal areas.
- Systemic symptoms (fever with or without lymphadenopathy) plus relevant exposure in the preceding 21 days: close physical/sexual contact with a suspected/confirmed case, travel to an affected area, or animal exposure.
- Atypical or localized presentations (for example, proctitis or pharyngitis/tonsillar lesions) when epidemiological risk exists - discuss with infection specialists if uncertain (UKHSA).
Triage and immediate ED actions
1. Rapidly isolate the patient in a single room with a closed door. Cover uncovered lesions with dressings or clothing where possible. 2. Apply contact and droplet precautions immediately: gloves, fluid-resistant surgical mask (FRSM), eye...