Canadian Researchers Uncover Sexual Transmission of Deadlier Mpox Strain

A joint Canadian-DRC research team, co-led by Jason Kindrachuk from the University of Manitoba, has documented what he calls a 'massive red flag': the first known cases of a deadlier strain of the mpox virus that is spreading through sexual contact.

In a significant development, Canadian scientists, in collaboration with international colleagues, have identified cases of a deadlier strain of mpox being transmitted sexually. This discovery, first reported by CBC News, marks a concerning evolution in the behavior of the virus.

The Research Findings

A joint Canadian-Democratic Republic of the Congo (DRC) research team, co-led by Jason Kindrachuk of the University of Manitoba, documented what Kindrachuk described as a “massive red flag.” According to the World Health Organization (WHO) and an upcoming paper, this team identified the first known cases of clade I mpox spreading through sexual contact. Clade I has a higher fatality rate than the clade IIb strain responsible for the 2022 global outbreak.

A child with mpox sits on his father’s lap while receiving treatment at the centre of the International medical NGO Doctors Without Borders in the Central African Republic. The World Health Organization has declared an end to the global public health emergency for mpox, yet some scientists warn there’s still cause for concern. (Charles Bouessel/AFP)

Details of the Cases

The paper details a case where a Congolese man, after having sexual contact in Europe, tested positive for clade I mpox upon his return to the DRC. He reported sexual contact with nine additional partners, resulting in five confirmed infections. This finding challenges the previously held notion that clade I mpox mainly spreads through close or surface-based contact.

Global Impact and Concerns

While the global attention on mpox has waned since 2022, the virus continues to pose significant health risks. The DRC, in particular, is experiencing its largest annual outbreak, with over 12,000 suspected cases and nearly 600 deaths this year. This development raises concerns about the broader geographical spread of both clades of mpox, especially in regions with internationally mobile populations.

A patient receives an mpox vaccination at a clinic in southern France in August 2022. While global cases of the virus are now dropping, some scientists warn mpox will remain a global threat, with future outbreaks a near certainty. (Pascal Guyot/AFP/Getty Images)

The Nigerian Connection

In Nigeria, another partnership between Canadian and local researchers, co-led by Rosemary Audu, is exploring the dynamics of mpox infections, including transmission patterns and potential animal carriers. This research aims to understand the virus better and identify ways to contain it effectively.

Expert Opinions

Kindrachuk emphasized the importance of continued vigilance and research, highlighting the disparity in vaccine availability between Africa and higher-income countries. Dr. Isaac Bogoch, working alongside Kindrachuk on DRC mpox research, echoed these sentiments, noting the increase in mpox cases in Africa since smallpox vaccination programs wound down.