By Fatih Erel

GENEVA

UN's health agency has begun vaccination for Ebola virus in the Democratic Republic of the Congo after an alarming outbreak killed at least 25 people, agency's chief said Monday.

"I am pleased to say that vaccination is starting as we speak," World Health Organization Director-General Dr. Tedros Adhanom Ghebreyesus told the opening of Who's six-day annual assembly in Geneva.

According to WHO, a total of 45 Ebola virus disease cases have been reported in the DRC, including 25 deaths from April 4 through May 17. Three healthcare workers were also among 25 deaths.

This is the DRC’s ninth Ebola outbreak since the discovery of the virus in the country in 1976.

"The International Health Regulations (IHR) Emergency Committee met on Friday and advised me not to declare a public health emergency of international concern, although they noted that the situation remains very serious. I have accepted that advice," he said.

"It is concerning that we now have cases of Ebola in an urban center, but we are much better placed to deal with this outbreak than we were in 2014," he said.

Ebola caused global alarm in 2014 when the world's worst outbreak began in West Africa, killing more than 11,300 people and infecting an estimated 28,600 as it swept through Liberia, Guinea and Sierra Leone.

EVD, formerly known as Ebola hemorrhagic fever, is a severe, often fatal illness in humans. The virus is transmitted to people from wild animals and spreads in the human population through human-to-human transmission.