Heavy-tailed sexual contact networks and the epidemiology of monkeypox outbreak in non-endemic regions, May 2022

[Shiloh]

Source: https://www.medrxiv.org/content/10.1101/2022.06.13.22276353v1


Heavy-tailed sexual contact networks and the epidemiology of monkeypox outbreak in non-endemic regions, May 2022
Akira Endo, Hiroaki Murayama, Sam Abbott, Ruwan Ratnayake, VCarl A. B. Pearson, W. John Edmunds, Elizabeth Fearon, Sebastian Funk
doi: https://doi.org/10.1101/2022.06.13.22276353
This article is a preprint and has not been peer-reviewed [what does this mean?]. It reports new medical research that has yet to be evaluated and so should not be used to guide clinical practice.
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Abstract

A global outbreak of monkeypox across non-endemic regions including Europe and North America was confirmed in May 2022. The current outbreak has shown distinct epidemiological features compared with past outbreaks in non-endemic settings, most notably its observed rapid growth and predominant spread among men who have sex with men (MSM). We use a branching process transmission model fitted to empirical sexual partnership data in the UK to show that the heavy-tailed nature of the sexual partnership degree distribution, where a small fraction of individuals have disproportionately large numbers of partners, can explain the sustained growth of monkeypox cases among the MSM population despite the absence of such patterns of spread in past outbreaks. We also suggest that the basic reproduction number (R0) for monkeypox over the MSM sexual contact network may be substantially greater than 1 for a plausible range of assumptions, which poses a challenge to outbreak containment efforts. Ensuring ongoing support and tailored public health messaging to facilitate prevention and early detection among MSM with a large number of sexual partners is warranted.

 

[Shiloh]

Source: https://www.science.org/content/article/monkeypox-outbreak-mostly-affecting-men-sex-men


Why the monkeypox outbreak is mostly affecting men who have sex with men
The virus did not spread well between people in the past but may have found a new niche in tightly connected sexual networks
20 Jun 202212:15 PM
ByKai Kupferschmidt

Ever since monkeypox started to sicken thousands of people worldwide this spring, two big questions have loomed: Why is a virus that has never managed to spread beyond a few cases outside Africa suddenly causing such a big, global outbreak? And why are the overwhelming majority of those affected men who have sex with men (MSM)?

A long history of work on sexually transmitted infections (STIs) and early studies of the current outbreak suggest the answers may be linked: The virus may have made its way into highly interconnected sexual networks within the MSM community, where it can spread in ways that it cannot in the general population.

An epidemiological modeling study posted as a preprint last week by researchers at the London School of Hygiene & Tropical Medicine (LSHTM) supports that idea. It suggests the outbreak will keep growing rapidly if the spread isn’t curtailed. It also has implications for how to protect those most at risk and limit spread, while suggesting the risk for the wider population remains low...