Author’s Note: This blog is written in coordination with co-authors Jason Yaun, MD, and Bindiya Bagga, MD, University of Tennessee Health Science Center, Department of Pediatrics, Memphis, TN.
Editor’s Note: The October 2024 issue of Pediatrics in Review contains an In Brief overview on Mpox (Monkeypox) Infection in Children, covering the epidemiology, clinical presentation, diagnosis, treatment, and complications of this increasingly global virus. Since the time the article went to press, a new outbreak has occurred.
In August 2024, mpox was declared a public health emergency of international concern by the WHO Director-General, following an increase in clade I mpox cases in the Democratic Republic of the Congo (DRC) and in the bordering countries.1
Which countries have reported mpox cases?
Mpox has been endemic to the DRC over the past decade, with a stable incidence prior to last year incidence began to increase. The current outbreak is spread across Central and East Africa (Burundi, Kenya, Rwanda, Uganda), parts of West Africa (Côte d’Ivoire), along with travel associated cases in Kenya, Thailand, and Sweden.1,2
Is this outbreak caused by a virus variant different from that of the 2022 outbreak?
Yes. Whereas the international outbreak in 2022 was caused by clade IIb, in the current outbreak the majority of cases have been reported to be caused by clade I. Clade I has been reported to cause more severe disease and mortality compared to clade II.3
What are the primary affected population and transmission routes in this current outbreak?
The pediatric population has been the most affected. More than 18,000 cases have been reported this year, with 67% of the cases occurring in children under 15 years of age3 and at least 600 deaths reported. Mpox is transmitted through close person-to-person contact. Although sexual transmission remains a reported mode of spread in this outbreak and dominates in certain regions of the DRC, the diverse demographic characteristics and genetic variations of the virus suggest that multiple transmission routes (including zoonotic, household, and sexual) are at play across different provinces, creating a complex epidemiological landscape.3
How do you treat monkeypox, and what is the current evidence supporting tecovirimat treatment of clade I mpox?
Most cases are treated with supportive care and pain control. The only available antiviral agent is tecovirimat, which is not yet approved for mpox by the Food and Drug Administration. It is used only in those with severe disease or those at risk for severe infections. Recently released preliminary results from the PALM 007 randomized clinical trial conducted in the DRC compared tecovirimat versus placebo and found tecovirimat to be well tolerated but it did not reduce the duration of mpox lesions among children and adults with clade I mpox infection.4 Further analyses are planned to better evaluate outcomes based on the duration of symptoms prior to enrollment, severity of clinical disease, participant characteristics, or the genetic variant of mpox.4
Is there a vaccine, and what are the updated indications for mpox immunization in the US?
JYNNEOS is a two dose vaccine series which protects against mpox and smallpox. The Centers for Diseases Control and Prevention (CDC) determined that, based on the ongoing human-to-human transmission of clade I mpox in Central and East Africa during the current outbreak, those who are planning to travel to affected countries with increased risk for sexual transmission of mpox should be offered vaccination with the 2-dose JYNNEOS series.5 Mpox immunization continues to be indicated as pre-exposure prophylaxis for individuals with high risk of sexually transmitted mpox, and post-exposure prophylaxis (as soon as possible but within 14 days) for children and adults with risk factors for complications and suspected or confirmed mpox exposure.5 Currently, the CDC does not recommend routine immunization for the general public or healthcare personnel unless sexual risk factors are present.
References
- Clade I MPOX outbreak originating in Central Africa (2024) Centers for Disease Control and Prevention. Available at: https://www.cdc.gov/poxvirus/mpox/outbreak/2023-drc.html (Accessed: 17 September 2024)
- Askling HH, Gisslén M, von Schreeb J. Mpox clade I outbreak and the first European case ex africa, in Sweden – a call for Global Health Equity. New Microbes New Infect. 2024:62;101465. doi:10.1016/j.nmni.2024.101465
- McQuiston JH, et al.S. preparedness and response to increasing clade I Mpox cases in the Democratic Republic of the Congo — United States, 2024. MMWR Morb Mortal Wkly Rep. 2024:73(19);435–440. doi:10.15585/mmwr.mm7319a3
- The antiviral Tecovirimat is safe but did not improve clade I mpox resolution in Democratic Republic of the Congo (2024) National Institutes of Health. Available at: https://www.nih.gov/news-events/news-releases/antiviral-tecovirimat-safe-did-not-improve-clade-i-mpox-resolution-democratic-republic-congo (Accessed: 17 September 2024)
- Vaccination | Mpox | Poxvirus | CDC (no date) CDC. Available at: https://www.cdc.gov/poxvirus/mpox/interim-considerations/overview.html (Accessed: 17 September 2024)
