This is the first case confirmed in the country amid a deadly outbreak in neighbouring Democratic Republic of Congo.
A child in Uganda has tested positive for Ebola in what is the first cross-border case of the deadly virus since an outbreak started in neighbouring Congo past year, Uganda's health ministry said late Tuesday, in a blow to efforts by health workers who for months sought to prevent contamination across the heavily travelled border.
Uganda has been on high alert since the outbreak in the eastern DRC, where more than 2,000 cases of the highly contagious virus have been recorded, two-thirds of which have been fatal.
The boy and his family crossed the border Sunday, and the case was confirmed at a rural hospital.
Uganda has had multiple outbreaks of Ebola since 2000. Health care workers have widely deployed an effective Ebola vaccine in the affected DRC areas and intensively worked to contain cases, but their response has repeatedly been hampered by violence from the many insurgency groups, including attacks on health care workers and facilities.
Confirmation of cross-border contamination is a blow to local health officials who have been monitoring the border and isolating probable Ebola patients.
She then tweeted that the country had moved into "response mode" following the incident.
The outbreak in DR Congo has become the second biggest in history, with a significant spike in new cases noted in recent weeks.
Uganda has already vaccinated about 4,700 health workers against the disease, the joint statement by WHO and Ugandan health officials said.
Nearly 1,400 people have died of the disease since August.