An Ebola outbreak which has killed at least 131 people in the Democratic Republic of Congo may be spreading faster than originally thought, a World Health Organization (WHO) representative has warned.
Dr. Anne Ancia told the BBC that the more the agency investigates, the clearer it becomes that cases have spread to other areas.
Officials said more than 513 cases were suspected in DR Congo as of Tuesday, while one person has died in neighbouring Uganda.
However, modelling by the London-based MRC Centre for Global Infectious Disease Analysis suggested there had been 'substantial' under-detection, and it could not rule out there have already been more than 1,000 cases.
WHO chief Tedros Adhanom Ghebreyesus expressed deep concerns regarding the scale and speed of the epidemic.
It is feared the outbreak may have been ongoing for several weeks before it was first detected on April 24th.
No vaccine exists for this strain of the Ebola virus, but the WHO is evaluating whether other drugs may provide protection.
Ancia noted that the Ituri province of DR Congo, which is the epicentre of the outbreak, is a very unsecured area with high population movement, complicating the investigation and control of the disease.
The outbreak has also spread to the province of South Kivu and a case has been recorded in Goma, DR Congo's largest city.
Countries across Africa are tightening border screens and preparing health facilities, with Rwanda closing its borders with DR Congo. An American citizen exhibiting symptoms has been evacuated from DR Congo for treatment.
The US Centers for Disease Control and Prevention (CDC) is also working to evacuate at least six other Americans who were exposed to the virus.
Symptoms for Ebola initially mimic those of the flu, causing fever, headache, and fatigue. The Bundibugyo strain responsible for this outbreak is rare and has previously caused two outbreaks, leading to a mortality rate of about one third of those infected.
