An unprecedented outbreak of mpox that has been raging in the Democratic Republic of Congo (DRC) over the past several months has, as feared, spread beyond its borders. Sequencing of the mpox viruses in three cases reported earlier this week in Uganda and Kenya has now confirmed all belong to a deadlier variant previously seen only in DRC.

“We warned everyone about it,” says Placide Mbala, an epidemiologist at the National Institute of Biomedical Research in Kinshasa. “People are very mobile at the eastern part of the country with great connection with neighboring countries. It was just a matter of time to start seeing cases in those neighbor countries.”

The World Health Organization (WHO) is appealing for more help after the troubling development, which it fears could be a precursor to a new mpox epidemic,  just two years after a milder strain spread worldwide.  “A further scaling up of the mpox response underway in affected countries is urgently needed amid the expanding outbreak,” said WHO Director-General Tedros Adhanom Ghebreyesus in a statement to ScienceInsider. Tedros noted that WHO is working with local health officials, the Africa Centres for Disease Control and Prevention (CDC), and international partners to slow transmission. “But much more funding for a comprehensive response, including for diagnostics, therapeutics and vaccines, is urgently needed,” he said.