Surveillance efforts against mpox are being ramped up globally, as trials for a new treatment showed disappointing results against the variant driving the current outbreak.

The European Centre for Disease Prevention and Control (ECDC) on Friday raised its risk level assessment for mpox, formerly known as monkeypox, from low to moderate. The decision came after Sweden reported the first case of clade Ib outside Africa.

Pakistan has also reported its first case of mpox, and China has announced it would begin screening travellers for the virus. The UK Health Security Agency said there were no cases of the virus in the UK and the risk was considered low but that planning was under way to prepare for any cases in the future.

The Stockholm-based ECDC said more imported cases to Europe were “highly likely”.

“Due to the close links between Europe and Africa, we must be prepared for more imported clade I cases,” ECDC director Pamela Rendi-Wagner said in a statement.