Johannesburg, As the World Health organization (WHO) prepared to announce end of Ebola outbreak, doctors in the Democratic Republic of the Congo on Friday reported a fresh case of Ebola.

It was the first such report in 52 days, and came just two days before the WHO was set to declare the official end of the outbreak.

"After 52 days without a case, surveillance and response teams on the ground have confirmed a new case of Ebola in DRC. We have been preparing for and expecting more cases," the WHO tweeted.

The WHO further said: "Unfortunately, this means the government of #DRC will not be able to declare an end to the #Ebola outbreak on Monday, as hoped. But WHO remains on the ground & committed as ever to working with the government, affected communities & our partners to end the outbreak".

"I am so sad," says Marie-Roseline Darnycka Bélizaire, an epidemiologist who has coordinated the WHO's Ebola response in northeastern DRC for two years, was quoted as saying.

According to Nature journal, experts have called the Ebola outbreak, which started in August 2018, one of the most complex health emergencies the world has ever seen.

"More than 2,270 people have died of Ebola — around two-thirds of the outbreak's reported infections. In addition, more than 70 responders and people with the disease were injured in targeted attacks by armed groups," the report mentioned.

Cases began dwindling in January this year, and until today, the most recent person with the disease was diagnosed on February 17.

"This case means that the 42-day count-down to an official declaration of victory must begin again," the report added.