Swedish health authorities announced on Thursday the detection of a variant of mpox, just a day after international health organizations declared a health emergency regarding the viral disease. This marks the first identification of this variant outside of Africa. The World Health Organization raised concerns on Wednesday about a burgeoning outbreak concentrated in the Democratic Republic of Congo that has begun to spread to countries previously unaffected by mpox.
The ongoing outbreak in Africa is primarily driven by virus versions classified as clade 1, including the offshoot known as clade 1b, which are linked to more severe illness and fatalities compared to the clade 2 variant that was responsible for the global outbreak in 2022.
According to Swedish officials, the infected patient had traveled to a region in Africa where clade 1 is prevalent and was diagnosed with this variant after seeking treatment in Stockholm. The patient is currently receiving care, as confirmed by Magnus Gisslen, the state epidemiologist from the Public Health Agency of Sweden.
While officials consider the risk to the general public to be low, reflecting the assessment of the European Centre for Disease Prevention and Control, they expect to conduct a new evaluation soon, as occasional cases related to travel are anticipated.
Gisslen remarked in a news conference that the discovery of this case in Sweden, or outside Africa, was not unexpected. He emphasized the need to neither overestimate nor underestimate the risks due to uncertainties involved, which is why they are taking the situation seriously.
During the previous global outbreak, Sweden reported approximately 300 cases of clade 2. Public health officials have noted that the high mortality rates associated with clade 1 versions may be attributed to infections among more susceptible populations, such as children in areas with inadequate healthcare systems, rather than differences inherent in the virus itself. The emergence of clade 1b is concerning due to its transmission through sexual contact, which poses a greater risk of crossing international borders.
The 2022 outbreak predominantly affected men who have sex with men, but the current epidemiological patterns in Africa differ. In the Democratic Republic of Congo, many clade 1 cases involve children who contract mpox through contact with infected animals or within their households. These children face increased vulnerability due to their living conditions in overcrowded homes or displacement camps amidst conflict, where accessing medical care and self-isolation can be challenging.
In regions that have not previously reported mpox, clade 1b infections are being transmitted sexually among female sex workers and their male clients, as well as among men who have sex with men. Experts express concern that individuals in these groups may avoid seeking medical care or vaccination due to stigma surrounding homosexuality and sex work, which is illegal in certain areas.
Jennifer McQuiston, incident manager for the clade 1 mpox response at the U.S. Centers for Disease Control and Prevention, noted that the global response to mpox has improved significantly, enhancing preparedness to manage potential spread as clade 1 variants emerge outside Africa.
During the initial outbreak, mpox was largely overlooked in public health discussions, with limited testing and vaccination capabilities. Currently, authorities are vigilant regarding mpox, equipped with improved surveillance and testing methods to identify the variants associated with infections. With increased experience in identifying contacts of confirmed cases, health officials can better prevent further transmissions. Additionally, there is heightened immunity in communities previously at risk due to past infections and vaccinations.