Mpox, previously known as monkeypox, has escalated to a global emergency as a new strain, Clade 1b, spreads rapidly through eastern DR Congo and neighboring countries. This emerging virus has raised several questions about its severity and transmissibility.

What We Know About Mpox Clades

Mpox is not just a single outbreak; it consists of three distinct clades, each affecting different regions and populations. Clade 1a continues to cause infections in western DR Congo, often linked to bushmeat consumption. Clade 1b, the new strain, has been observed in eastern DR Congo and adjacent countries, primarily spreading through sexual contact and affecting sex workers and their clients. Clade 2, which caused a global outbreak in 2022, remains active, primarily impacting men who have sex with men.

Spread and Impact of Clade 1b
Clade 1b’s emergence has triggered international concern. The strain, first identified in Kamituga, South Kivu, has spread to Burundi, Kenya, Rwanda, and Uganda. This outbreak is marked by severe rashes and prolonged illness, with no links to bushmeat, distinguishing it from Clade 1a.

Transmission and Severity
The rapid spread in areas with high sex industry activity suggests that close contact, rather than increased virus transmissibility, is driving the outbreak. Current data on the virus’s mortality rate is incomplete, but Clade 1a has historically been more deadly. While smallpox vaccines offer some protection, targeted interventions are crucial to control the outbreak.

Global and Local Responses
While Mpox is unlikely to reach the severity of COVID-19, vigilant monitoring and response are necessary. The UK and other countries are focusing on contact tracing and vaccination rather than mass immunizations. Meanwhile, the situation in DR Congo is compounded by conflict and limited healthcare resources.