Health officials reported on Saturday that a 12-year-old girl died of the deadly Ebola virus about 35 kilometres (22 miles) north of Kampala.
Preliminary testing carried out at the Uganda Virus Research Institute showed on Friday that the girl died from the virus on May 6 at Bombo hospital, said Dr Miriam Nanyunja, disease prevention and control officer for the World Health Organisation in Uganda.
"She came into the hospital and died a few hours later," Nanyunja said. "They tested for Ebola and the confirmatory result came out yesterday."
Nanyunja said that health officials were currently looking for more cases in the area and planned to set up an isolation unit at Bombo hospital in anticipation of new patients.
Ugandan director general of health services Dr Nathan Mugisha confirmed the preliminary results and said that a taskforce was meeting on Saturday to work out how to deal with any potential outbreak.
"So far it is only preliminary test results and there is a meeting in progress," Mugisha told AFP.
The rare haemorrhagic disease, named after a small river in neighbouring Democratic Republic of Congo, killed 37 people in western Uganda in 2007 and claimed the lives of at least 170 people in the north of the country in 2000.