A frontline perspective on an emerging STI and sexual-health issue, drawing on clinical implementation experience among GBMSM in Kenya
Mpox is a vaccine-preventable viral infection that can cause painful skin and mucosal lesions and, in some people, severe complications. It spreads mainly through close contact, including skin-to-skin and sexual contact. Diagnosis relies on laboratory testing, while management is primarily supportive, including pain control, skin care and management of complications. Vaccines are available for people at increased risk of exposure to prevent infections or lessen the severity of symptoms.
At Health Options for Young Men on HIV/AIDS and STIs (HOYMAS), a Gay Bisexual and other Men who have Sex with Men (GBMSM)- led sexual-health clinic in Nairobi, what has stood out is not simply the rash, but severe anal, perianal and genital ulcerations with intense pain. This matters because anogenital Mpox can overlap with other STIs, may be missed without appropriate genital, perianal and anal examination, and can significantly disrupt daily functioning.
These presentations also reveal an important gap in Mpox care: severe anogenital disease may be missed when clinical assessment focuses mainly on visible skin lesions without comprehensive anogenital examination. The World Health Organization notes that Mpox spreads mainly through close contact, including sexual contact, which makes recognition of anal and genital presentations especially important within sexual-health services. This blog highlights why Mpox recognition and management need to be more fully integrated into STI and sexual-health services, particularly for populations at increased risk of exposure.
From early July to mid-August 2026, 20 clients were laboratory-confirmed positive for Mpox at HOYMAS, with new cases continuing to present. Common symptoms included skin lesions, fever, headache, body weakness, swollen lymph nodes and varying levels of pain.
Beyond the visible rash
Lesions appeared on the face and head, neck, hands and arms, shoulders, chest, abdomen, back, thighs and buttocks. In many clients, these were moderate to severe. In contrast, disease affecting the anal, perianal and genital areas was more severe, extensive and advanced.
Seventeen clients presented with severe anal or perianal ulcerations, while two had severe genital ulcerations or sores. Only one had no anogenital involvement. Clients with severe anal and perianal disease experienced intense pain, difficulty walking and sitting, painful passage of stool and disturbed sleep. Some could barely sit during consultation and preferred to remain standing. The anal and genital ulcerations were extensive, with discharge and smell, causing considerable discomfort and distress.
For most clients, the anal or genital symptoms were what brought them to the clinic. They were aware of lesions elsewhere but had not recognised them as Mpox-related.
This experience has challenged us to think differently about severity. Mpox cannot be understood only by counting lesions. Anatomical location, ulceration, pain and the effect on daily functioning matter.
Why this belongs within the STI response
For a sexual-health clinic serving GBMSM, these presentations are particularly important.
Severe anal, perianal and genital ulcerations can overlap with conditions commonly encountered in STI services. Without careful examination and laboratory testing, Mpox may be missed or initially managed as another condition.
Some clients had sought care elsewhere before reaching our sexual health clinic. In some instances, they had been treated for other conditions, including chickenpox, without a genital, perianal or anal examination. By the time they reached us, some anogenital ulcerations were already extensive.
These experiences reinforce the importance of taking a respectful, comprehensive sexual history and conducting genital, perianal and anal examination when clinically indicated. This echoes my longstanding HPV and anal-health advocacy, which has challenged stigma around anal examination, investigation and treatment.
Clinicians should also not assume that every anal or genital symptom in a client with confirmed Mpox is caused by Mpox. Other STIs and possible co-infections still need to be considered and investigated.
Mpox is, therefore, not only a dermatological or outbreak issue. For some GBMSM, it presents through the same anal and genital symptoms that bring clients into STI and sexual health services.
What may be shaping severe presentation?
Several recurring factors have surrounded these cases. Recent sexual contact and condomless sex were commonly reported. HIV infection was also frequent: 18 of the 20 confirmed cases were among people living with HIV, including three newly diagnosed clients. Two of these had CD4 counts below 200 cells/mm³. Nineteen of the 20 confirmed cases had anogenital involvement.
Limited knowledge about Mpox also appeared important. Clients could recognize skin lesions but did not necessarily know they could be Mpox-related. Others had sought care elsewhere but had not received an assessment that identified the anogenital lesions.
Most clients reported buying painkillers before coming to the clinic, reflecting how prominent pain has been, especially with severe anal and genital ulcerations.
Together, these experiences raise questions about delayed recognition, access to appropriate services, HIV-related immunosuppression and how quickly severe anogenital disease may progress before clients reach appropriate care.
Diagnostic and management challenges from the frontline
The cases have exposed practical challenges for providers. Collecting samples from severe and painful anal and genital ulcerations can be difficult and uncomfortable. The location and extent of disease can limit what samples can reasonably be obtained, particularly during the acute phase.
Providers also need clearer guidance for managing severe anogenital Mpox: how severity should be assessed, how severe pain should be managed, when referral or admission is required, how suspected bacterial superinfection should be approached, how often clients should be reviewed and how management should differ for people living with HIV or significant immunosuppression.
From the frontline, these are not theoretical questions. They affect decisions made for individual clients every day.
To strengthen surveillance and generate preliminary evidence, HOYMAS is working with the Partners for Health and Development in Africa (PHDA) and the University of Manitoba to collect additional biological samples from consenting clients. These include blood samples for full haemogram, or complete blood count, Rapid Plasma Reagin and immune profiling, as well as rectal, genital and lesion swabs for viral characterization and DNA sequencing to better understand circulating Mpox strains.
What needs to change
The cases point to several priorities. Clinicians need guidance that recognizes severe anal, genital and other mucosal presentations—not only generalized skin disease. Sexual-health providers need to be comfortable taking respectful sexual histories and performing genital, perianal and anal examinations when indicated.
Community education should make it clear that Mpox can involve the anal and genital areas so people recognize symptoms earlier and seek timely care.
For policymakers, practical standardized guidance is urgently needed, including approaches to severity assessment, pain management, sampling, referral, follow-up and management of people living with HIV.
Mpox prevention must also include equitable vaccine access. Although vaccines are available, access remains uneven across Africa. High-risk populations and others with increased exposure should have timely access as part of a comprehensive mpox response. Advocacy should therefore focus on both clinical management and vaccine equity.
The response must recognize patterns of sexual transmission without turning affected communities into the problem.
Conclusion
The cases seen at HOYMAS remind us that Mpox is not only a generalized rash illness. For some GBMSM, the most clinically significant manifestation may be severe anal and genital ulceration associated with intense pain and substantial disruption of daily life.
Recognizing these presentations early requires more than looking for a rash. It requires careful sexual history-taking, appropriate genital and anal examination, laboratory testing, consideration of other STIs and clear pathways for management and referral.
What we are seeing at the frontline should inform what happens next. Clinicians need practical guidance, programmes need stronger integration of Mpox within HIV and STI services, and policymakers need to ensure national responses reflect the presentations occurring in real clinics and communities.
About the Author
Samuel Anyula Gorigo, BScN, is a global health practitioner, HIV clinician, implementation science and research professional, and health policy advocate with over seven years of experience in HIV prevention and treatment, STI care, sexual and reproductive health, anal health, HPV prevention and key-population health. At HOYMAS Kenya, he leads the clinical arm, bridging frontline clinical service delivery, community-led programming, research, health-systems strengthening and policy advocacy, with a particular focus on improving equitable and stigma-free services for gay, bisexual and other men who have sex with men and other key populations. He has contributed to the development and implementation of anal-health service models, including Kenya’s first Anal Health Examination SOPs and HPV screening tools for GBMSM- clinical tools, and national HIV/STI policy and guideline processes in Kenya. He is a former AVAC Advocacy Fellow; he has authored peer-reviewed publications, and currently contributes to frontline mpox clinical documentation and research at HOYMAS, including collaborative work with PHDA and the University of Manitoba on severe anogenital mpox presentations, HIV co-infection, immune profiling and viral characterization.
