A five-year-old boy is being treated for Ebola in Uganda, the very first case since an outbreak in neighbouring Democratic Republic of Congo 10 months ago, the World Health Organisation said on Tuesday.

"The confirmed case is a 5-year-old Congolese child who travelled from the DRC with his family on June 9. The child and his family entered the country through Bwera Border post and sought medical care," the WHO wrote on Twitter.

Uganda's health ministry and the WHO have sent a team to the western town of Kasese to trace likely cases, and vaccinate those who may have come into contact with the patient, the post added.

Uganda has been on high alert since the outbreak in the eastern DRC, where more than 2000 cases of the highly contagious virus have been recorded, two-thirds of which have been fatal.