The World Health Organization said Friday it was preparing for "the worst case scenario" in a fresh outbreak of Ebola in the Democratic Republic of Congo.
"We are very concerned, and we are planning for all scenarios, including the worst case scenario," WHO's head of emergency response Peter Salama told reporters in Geneva.
WHO has tallied 32 suspected or confirmed cases in the northwestern area of Bikoro, on the shores of Lake Tumbathe near the border with the Republic of Congo, including 18 deaths, between April 4 and May 9.
The cases include three healthcare workers, one of whom has died, Salama said.
The outbreak, declared by the DRC health ministry on Tuesday, is the country's ninth known outbreak of Ebola since 1976, when the deady viral disease was first identified in then-Zaire by a Belgian-led team.
Ebola is one of the world's most notorious diseases, being both highly infectious and extremely lethal.
Salama said the strain raging in Bikoro was the Zaire strain, which also was responsible for the recent west Africa epidemic that killed more than 11,300 people.
He said the affected region of the vast strife-torn central African country is very remote and hard to reach.
This could have a benefit since it could slow down the spread of Ebola, but it also greatly complicates the response.
Looming urban outbreak?
"It is an absolutely dire scene in terms of infrastructure," Salama said.
"There are very few paved roads, very little electrification," he said, adding that "access is extremely difficult... It is basically 15 hours by motorbike from the closest town."
At the same time, cases have already been reported in three separate locations around Bikoro, and Salama warned there was a clear risk the disease could spread to more densely populated areas.
WHO is particularly concerned about the virus reaching Mbandaka, the capital of Equateur province, which has around one million inhabitants and is only a few hours away from Bikoro.
"If we see a town of that size infected with Ebola, then we are going to have a major urban outbreak," Salama warned.
In addition, he said the surrounding nine countries had been put on "high alert". The WHO was especially concerned about the possible spread to neighbouring Republic of Congo and the Central African Republic, which have connections to the affected area through the river systems.
He said the possibility of international spread of the disease was still considered "low", but that the situation was constantly being evaluated.
WHO already has a team on the ground and is preparing to send up to 40 more specialists in epidemiology, logistics, contact tracing and other areas to the region in the coming week or so.
The UN health organisation also hopes to have a mobile lab up and running on site this weekend, Salama said.
At the same time, WHO and the World Food Programme are working to set up an "air-bridge" to help bring in the supplies needed, he said, adding though that only helicopters could be used until an airfield could be cleared to allow larger planes to land.
The response "is going to be extremely challenging, and very costly," he said.
The WHO is meanwhile awaiting a green light from DRC authorities to begin a vaccination campaign in the area, using an available stockpile of an experimental vaccine.
Salama said the WHO and others were doing the groundwork of tracking down contacts of those infected to be able to quickly put in place a so-called ring vaccination campaign once they get the go-ahead.
He stressed however that "this is an experimental vaccine", pointing out that it must be stored at temperatures as low as minus 80 degrees Celsius (-112 degrees Fahrenheit).
"This is not a simple logistical effort... This is a highly complex, sophisticated operation in one of the most difficult terrains on earth."
At the same time, Salama insisted that "the Ebola vaccine is not a magic bullet."
"The basic bread and butter of epidemiology, of finding cases, finding contacts, isolation and regular support and care, community mobilisation are what will break the back of this (outbreak). The vaccine is an added tool."
The worst-ever Ebola outbreak started in December 2013 in southern Guinea before spreading to two neighbouring west African countries, Liberia and Sierra Leone, killing more than 11,300 people out of nearly 29,000 registered cases.
The UN health agency faced harsh criticism for responding too slowly and failing to grasp the gravity of that outbreak until it was out of control.
Salama insisted Friday that the UN agency's response this time was "very different".
WHO immediately jumped into action once the outbreak was declared, he said, and was currently in "full surge capacity".
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