KINSHASA, Dec. 23 (Xinhua) -- The epidemiological situation of Mpox in Africa remains "especially concerning," with high case counts observed in the Democratic Republic of the Congo (DRC), Burundi, and Uganda, the World Health Organization (WHO) said Monday.

According to the latest report of the WHO, Africa has seen 13,769 confirmed cases across 20 countries as of Dec. 15, including 60 deaths. The most affected country continues to be DRC, with 9,513 confirmed cases detected.

While the DRC, the outbreak's epicenter, has seen a relatively stable epidemic trend in recent weeks, WHO still warned that the plateauing and declining trends should be interpreted cautiously, given possible reporting delays.

The latest outbreak features the emergence and spread of a more dangerous but poorly understood variant, clade 1b, first detected in the DRC in September 2023. Cases of this clade 1b strain have since been reported in several countries, including Sweden and Thailand.

"Geographical expansion of clade 1b mpox virus (MPXV) continues to be reported outside the DRC," the WHO said, noting that eight countries outside of Africa have detected the strain.

Mpox is a viral illness caused by the monkeypox virus, which has two distinct clades, including clade 1b and clade 2b, and can be transmitted to humans through physical contact with an infectious person, contaminated materials, or infected animals.

"Much remains to be understood about the transmissibility and sustainability of transmission of the clade 1b MPXV," said the WHO, which specified earlier that the mortality rate of the clade 1b MPXV was estimated at 3.6 percent, much higher than previous strains. ■