HTB

Glasgow 2022: Mpox updates on epidemiology, treatment and prevention

1 December 2022. Related: Conference reports, mpox (monkeypox).

Kirk Taylor, HIV i-Base

HIV Glasgow 2022 included an in-depth symposium on the monkeypox outbreak – newly renamed mpox – that included talks from healthcare professionals, reflections from a patient and survey data. [1–6]

Although by 28 November 2022, 3,575 confirmed cases of mpox had been reported in the UK, numbers have dramatically dropped to less than 30 over the last month. [7] Mpox case numbers across Europe peaked in the summer and are now in similar decline. [1]

Guidelines for mpox presentation have been updated to include anogenital and mucosal lesions and reference sexual transmission routes. [2]

People living with HIV account for 38% of mpox cases and CDC guidelines state that those with <200 CD4 cells/mm3 should be prioritised for both vaccination and access to tecovirimat. [2, 3]

Harun Tulunay gave a powerful account of his experience with mpox and stressed the need to promote vaccine uptake and adequately support sexual health services. [4]

Survey results cited high levels of early mpox awareness but highlight inequities in the mpox response linked to education and employment status. [5, 6]

Epidemiology of the mpox outbreak

As of October 2022, WHO figures include 25,036 confirmed mpox cases across 41 European countries. [1, 2]

Countries with the greatest number of cases are Spain (7,277), France (4,084), United Kingdom (3,686) and Germany (3,651). Mpox evolution has been quicker than anticipated with 50 mutations to date (compared to the expected 4). Mutations within APOBEC3 likely account for reduced pathogenicity and increased mpox distribution.

Across Europe, 39% of cases were reported for people aged between 31 to 40 and males account for 98% of all cases. Of those, the majority were gay and bisexual men (96%) and 38% were people living with HIV.

International case definitions were updated in May 2022 to include sexually active gay and bisexual men.

Case data from the UK, Spain, CDC and a global study were used to explore mpox presentation and symptoms. Early associations were drawn between mpox and transmission, sexual contact, sex-on-premises venues, HIV, large gatherings (e.g. pride) and travel.

Onset of mpox symptoms took a median of 7 days and included rash (96%), systemic symptoms (68%) and anogenital lesions (49%). Hospitalisation rates were 6.3% (n=736) with 5 people admitted to the ICU and 4 deaths.

Clinical definitions have been updated to include anogenital and mucosal lesions.

Decline in mpox cases is likely due to early diagnosis, contact tracing, awareness programmes and vaccinations. The impact of each measure and how the mpox outbreak will develop remains unclear. [1]

Data from London indicate that the reduction of mpox cases preceded peak vaccine uptake, suggesting behavioural changes were likely a key factor in reducing case numbers. [3]

Mpox and people living with HIV

Given that mpox virus has been detected in semen, swabs (urethral and anal), and type of sex correlates with lesion sites, Professor Chloe Orkin was one of the leading doctors proposing that mpox should be classified as an STI. This was reflected in an updated Swiss statement on mpox that says, “MPX must for now be considered an STI but it is important to note that transmission can still occur outside of sex”. [2]

People living with HIV are disproportionately affected by mpox and whilst the underlying reasons are unclear, this may arise through behavioural differences relating to risk, easier access to testing and biological factors.

Although a retrospective review of people hospitalised with mpox in Nigeria reported 9/40 cases were people living with HIV, the majority were not virally suppressed and 4/9 had <200 CD4 cells/mm3. People living with HIV had more prolonged illness with larger and more widespread lesions and higher incidence of bacterial superinfection. [8]

Data from the US CDC report no differences in clinical presentation or hospital admissions for those who were HIV positive (n=201) with a median CD4 count of 680 cells/mm3 and virological suppression rate of 97%. There were two cases with significant complications of epiglottitis and myocarditis.

Racial disparities are highlighted within the CDC data with higher than expected case rates for Black, Asian and Latinx populations. 82% of people in the data series were virologically suppressed but those who were HIV positive were more likely to be hospitalised with mpox than HIV negative people (8% vs 3%).

US CDC guidelines indicate that PLWH <200 CD4 cells/mm3 are at higher risk of severe complications and should be prioritised for vaccination and tecovirimat. Intradermal dosing is not recommended with <200 CD4 cells/mm3. Vaccination in the UK has been prioritised for healthcare workers and sexually-active gay and bisexual men. [2, 3]

Mpox vaccines and therapies for treatment and prevention

Orthopox viruses have shared immune epitopes and three smallpox vaccines are licenced for use against mpox. The MVA-BN-Jynneos formulation (non-replicating virus) is most widely used and is non-inferior to the live vaccine (ACAM2000) which is not being used due to higher toxicity.

A single dose generates T and B cell responses but efficacy data against mpox are limited. Open-label observational data on mpox vaccination from the US CDC show that unvaccinated individuals were 14 times more likely to contract mpox, but this doesn’t account for behavioural differences and vaccine use. A much smaller observational cohort in Israel reported vaccine efficacy of 80% after a single dose, but with similar cautions about interpretation of non-randomised data. [3]

Interestingly, healthcare workers who had previously been vaccinated against smallpox had neutralising antibody responses to mpox. Neutralisation titres were lower for people that had not previously been vaccinated against smallpox.

Antivirals for mpox include tecovirimat, cidofovir and brincidofovir and interactions with ART are available through the University of Liverpool site. [9]

Tecovirimat has been used in the UK for people hospitalised with mpox. Although the UK PLATINUM and US STOMP trials are ongoing to evaluate tecovirimat, enrolment is now challenged by having dramatically fewer cases.

Living with mpox, the patient perspective

Harun Tulunay, an HIV-positive advocate at Positively UK in London gave a powerful talk, outlining his early experience of mpox, symptom progression, and the difficulty in getting a diagnosis. Harun’s first symptom in June 2022 was a single facial lesion on his nose accompanied by a high fever. He ascribed the lesion to impetigo and tested several times for COVID, all were negative. [4]

Ibuprofen was used to manage early symptoms and he began to experience muscle pains and a sleep-disturbing rash. This was diagnosed as a fever rash. It took 2.5 weeks and six calls to emergency services before paramedics came to his flat. They advised him to take analgesics, anti-inflammatories, and penicillin for tonsilitis.  Harun’s GP wrongly suggested his ART may have stopped working.

After he was hospitalised due to oropharyngeal lesions that prevented him swallowing food and fluids, he received tecovirimat. After three days he was able to swallow and was discharged on day 10.

Harun was very open and transparent about his experiences, and broadcasting a blog on YouTube, contributed to early behaviour changes in the community. He then developed online support groups and awareness campaigns.

This led to both positive and negative messages in response to his campaigns. He stressed that five months into the mpox outbreak, half of those eligible are unvaccinated and that sexual health services should have been more adequately supported.

Perceptions of mpox

Between June and July 2022, two UK community surveys examined awareness and understanding of mpox. [5, 6]

Surveys were distributed through social media and Grindr. Respondents (n=1932) were male (91%), aged <40 (39%), White (71%), Asian (8%), Black (3%) and Latinx (2%). 90% of respondents were cis or trans men who have sex with men and 77% of all respondents identified as gay or lesbian and 7% were living with HIV.

Awareness was high with only 31 individuals reporting that they had not heard about mpox. News outlets were the most common source of information (57%), followed by Twitter (21%), dating apps (13%) and healthcare professionals (11%). About half the respondents did not feel that those talking about mpox represented them (45%).

Healthcare professionals and government websites were considered the most credible sources of information. Social media and private group chats scored low on trustworthiness.

Only 17% of respondents said that they understood mpox ‘very well’ and understanding was greater for Latinx than Black respondents (35% vs 12%). Greater educational attainment and being employed also correlated with understanding.

Over half of respondents considered themselves at risk of mpox and 50% said that they would attend a sexual health clinic if they experienced mpox symptoms. 38% said they would be unable to isolate for 21 days, citing lack of support and disability amongst their reasons. 6% of people said that they would not receive a vaccine if it was available to them.

A sub-analysis of cis (n=88) and trans (n=15) women was conducted. [6] Although this group had high rates of vaccine acceptability, public health information and advice were neither universally accepted nor correctly understood. There is a risk of compounding health inequalities and engagement with all communities is required.

References

Presentations 1-6 were part of a symposium on the mpox outbreak presented at HIV Drug Therapy, Glasgow, 23 to 26 October 2022.

The session webcast is available through the conference platform:
https://virtual.hivglasgow.org/programme/monkeypox-where-are-we-now-and-what-have-we-learned

The abstract book is available here:
https://onlinelibrary.wiley.com/doi/10.1002/jia2.26009 (abstracts)

  1. Noori T. Epidemiology of monkeypox and public health response. HIV Drug Therapy, Glasgow, 23 to 26 October 2022).
  2. Orkin C. Case definitions, evolution and HIV presentation. HIV Drug Therapy, Glasgow, 23 to 26 October 2022).
  3. Bhagani S. Treatment, vaccines and guidelines. HIV Drug Therapy, Glasgow, 23 to 26 October 2022).
  4. Tulunay H. The patient perspective. HIV Drug Therapy, Glasgow, 23 to 26 October 2022).
  5. Paparini S. Perceptions and understandings of media and public health messaging about the monkeypox outbreak in the UK: Findings from a rapid response, co-produced survey. Oral 41A. HIV Drug Therapy, Glasgow, 23 to 26 October 2022).
  6. Paparini S. Including women in the public health response to the monkeypox (MPXV) outbreak in the UK: Findings from a rapid response, co-produced survey. Oral 41B. HIV Drug Therapy, Glasgow, 23 to 26 October 2022).
  7. UKHSA. Monkeypox outbreak: epidemiological overview, 29 November 2022.
    https://www.gov.uk/government/publications/monkeypox-outbreak-epidemiological-overview/monkeypox-outbreak-epidemiological-overview-29-november-2022
  8. Ogoina D. Clinical course and outcome of human monkeypox in Nigeria. Clin. Inf. Dis. 71(8). (13 February 2020).
    https://doi.org/10.1093/cid/ciaa143
  9. Liverpool University Drug Interaction Website.
    https://www.hiv-druginteractions.org/checker

Links to other websites are current at date of posting but not maintained.