Implications for practice and research

• This paper describes new signs and symptoms of the 2022 monkeypox outbreak among gay, bisexual and other men who have sex with men (GBMSM) in non-endemic countries, urgently needed by clinicians, public health practitioners and GBMSM. GBMSM need access to smallpox vaccination, alongside public health messaging to enable us to recognise monkeypox, understand preventative behaviours, seek treatment and manage self-isolation. This is essential to prevent outbreaks to wider populations and avoid overwhelming the NHS yet must avoid further stigmatising GBMSM.

• Accordingly, research is urgently required to understand monkeypox transmission networks among GBMSM, clarify transmission routes for this new outbreak and co-produce effective behavioural prevention strategies.

Context

Over 41 000 monkeypox cases across 96 non-endemic countries have been observed since May 2022, with 95.8% of cases occurring among gay, bisexual and other men who have sex with men (GBMSM).1 In the UK, 3279 cases of monkeypox were confirmed in the past 4 months, almost all GBMSM, with 70% in London.2 In contrast, far fewer cases have been recorded within endemic countries. ‘Classic’ monkeypox manifests as fever, malaise, sweats, swollen lymph nodes and headache followed by skin lesions typically on the face, palms, soles, mucous membranes and less commonly the genitals. In their paper, Patel et al document how the clinical features of the novel 2022 monkeypox outbreak differ markedly from classic monkeypox.

Findings

All participants were men, median age=38 years and 99.5% identified as GBMSM. Unlike classic monkeypox, 88.3% of participants presented lesions on the genitals, anus/perianal area or both. Most participants reported systemic illness (86.3%), typically fever (61.9%), swollen lymph nodes (57.9%) and muscular pain (31.5%). One-third (38.5%) developed skin lesions prior to bodily illness, some (13.7%) had lesions without other symptoms and one-third (36.0%) reported rectal pain. Most (96.0%) reported sex with male partners within 21 days of symptoms, one quarter (26.5%) reported close contact with someone with monkeypox and a quarter (27.4%) had recently travelled abroad (mainly European countries). One-third (35.5%) had HIV and almost one third (31.5%) tested positive for a concomitant sexually transmitted infection. In total, 10.2% were admitted to hospital because of their monkeypox symptoms, mainly rectal pain and penile swelling. Complex presentations of monkeypox infection are further discussed in the paper, with corresponding images.

Commentary

This study specifies the key signs and symptoms of the 2022 monkeypox outbreak in western countries. Crucially, there are clear differences between this and previous outbreaks of classic monkeypox within endemic regions; (1) this outbreak has primarily infected GBMSM and is not associated with travel to an endemic country; (2) some common symptoms are not included within current monkeypox public health messaging and diagnostic criteria, specifically rectal pain, penile swelling and anogenital lesions, while lesions may precede other bodily symptoms. Although this study provides evidence that monkeypox remains a largely self-limiting illness, with a low fatality rate, 1 in 10 patients require admission for symptom care and serious complications have also been observed.

This paper has important implications for public health and clinical services. It provides updated advice crucial for clinicians to understand the current outbreak, clarifies the importance of sexual partner contact tracing and underscores the urgent procurement and delivery of the smallpox vaccine to GBMSM most at risk of infection. Furthermore, clear and consistent public health advice, ideally co-created, is needed for GBMSM to recognise monkeypox, seek treatment, support self-isolation, understand transmission routes, clarify preventative behaviours and encourage vaccination uptake.3 This is especially important since the traditional ‘safer sex’ message of condoms/lube and more recent biobehavioural HIV prevention (such as pre-exposure prophylaxis (PrEP) and treatment as prevention (TasP)) are ineffective here. Given the multiple health inequalities already effecting GBMSM, this must be done without further stigmatising or pathologising our community. Accordingly, biobehavioural surveillance research is urgently needed to understand monkeypox transmission networks among GBMSM and clarify transmission routes for this new outbreak, alongside intervention development research to co-produce, then evaluate, effective behavioural transmission prevention strategies. Without these measures, monkeypox could also spread to other groups (especially vulnerable individuals such as children, the elderly, immunocompromised people and healthcare professionals) and risks overwhelming the NHS, which is already at breaking point.