A Congolese woman who may have spread the deadly Ebola virus in Uganda did not go to Rwanda or the Congolese city of Goma while contagious, the World Health Organization (WHO) said on Friday.

On Thursday, a report written by Uganda's Health Ministry and published by the WHO's Africa office had said the woman, a fishmonger, was suspected of going to Goma and Rwanda as well as Uganda before she died.

That raised fears of the outbreak spreading in Rwanda, which has never had a recorded case of Ebola.

But the WHO later withdrew the report and shut down the website where the daily updates were being posted, saying some of the information had not been verified.

"We have investigated fully, and there was no travel to anywhere but Uganda," WHO spokesperson Margaret Harris said, adding that inaccurate conjecture had unfortunately found its way into the reports.

Healthworkers have mounted a massive campaign of vigilance and vaccination on key routes and borders in the region, and have screened almost 75-million people since the outbreak was declared 11 months ago. It has killed more than 1 700 people.

The 22-year-old woman was thought to have crossed the border between Uganda and Congo at an unmonitored crossing point, the deleted reports said. Harris said there no chance she had also slipped into Rwanda without being spotted.

"We are absolutely certain," she said. "Our team... went across and talked to everybody and tracked it day-by-day. Now in her life she may have gone to Rwanda... but the important thing is she did not spend any time in Rwanda while symptomatic."

It was extraordinary that a woman with end-stage Ebola had managed to cross the border and sell fish for a day, she added.

A lot of people at potential risk were now being followed up and people were being vaccinated on both sides of the border, Harris said. But it would take several days before it became clear if the woman, who vomited several times at a market, had infected anyone.

Other details in the withdrawn reports were also unverified, including information about a second Congolese Ebola patient travelling to the same market, and about a group of Ugandan healthworkers who may have been exposed to Ebola.