The head of the World Health Organization said Monday that the fast-moving Ebola outbreak in Democratic Republic of Congo and Uganda is outpacing response efforts, with the number of suspected deaths now at 220.

Addressing an online meeting of the African Union, WHO Director-General Tedros Adhanom Ghebreyesus said a delay in detecting cases means responders are "playing catch-up" and the epidemic is likely to get worse before it gets better.

Tedros said he will travel to Congo on Tuesday with another senior WHO official, Chikwe Ihekweazu.

Neighboring Uganda reported two more Ebola cases Monday, bringing its total to seven. Tedros says other countries bordering Congo are at high risk and should take immediate action.

The WHO has declared the rare Bundibugyo strain a public health emergency of international concern. Tedros notes that containment is complicated by insecurity in Congo's Ituri and North Kivu provinces and the lack of approved vaccines for Bundibugyo.