Uganda has vaccinated thousands of health workers against Ebola to counter the spread of the deadly virus from its neighbour Democratic Republic of Congo, the health ministers of both countries said on Wednesday.

A growing outbreak of Ebola in the Beni region of eastern DRC, just 50km from the Ugandan border, has claimed some 268 lives among a total of 453 cases, according to figures released Tuesday from the DRC health ministry.

Uganda, which last month announced the plan to roll out the vaccinations for frontline health workers over fears the virus could spread, said on Wednesday that it had already given the precautionary treatment to 3 000 people "because we are worried".

"We have not waited for the first case to arrive. The vaccination is continuing," said Ugandan Health Minister Jane Ruth Aceng, at a joint briefing with her Congolese counterpart Oly Ilunga in Goma.

Thousands of people cross the 15 border points between the two countries, particularly on midweek market days, she added.

Giving an update on DRC's own vaccine drive, Ilunga said authorities had given the treatment to some 38 000 people.

"If there were no vaccines, half of those would have developed the illness, we would be at tens of thousands of victims and of deaths," he estimated.