Global health teams battling the world’s second largest Ebola epidemic in Democratic Republic of Congo fear an election dispute may deepen public mistrust and allow the epidemic to run out of control.

Fostering confidence in health authorities is essential when fighting a disease that can spread furiously through communities where local services are scant and patients are often scared to come forward to government or international response teams.

“When you have political instability, public health always suffers,” said Jeremy Farrar, an infectious disease expert who recently visited east Congo with a World Health Organization leadership team.

Without public trust, he said, the Congo epidemic could kill many hundreds more people.

The December 30 election was supposed to mark Congo’s first uncontested democratic transfer of power after 18 years of chaotic rule by President Joseph Kabila.

But accusations of fraud and calls for a recount arethreatening more volatility and violence after opposition leader Felix Tshisekedi was declared winner.

“The worst case scenario is that political instability remains, mistrust grows and then there’s nothing to stop the epidemic getting embedded into a big urban centre and taking offas it did in West Africa,” said Farrar.

Already, 385 people have been killed in the outbreak of Ebola in east Congo that began six months ago and has infected atleast 630 people, according to WHO data.

The death rate in this epidemic is by far the biggest Congo has seen and the world’s second largest in history.

Ebola spreads through contact with bodily fluids. It causes hemorrhagic fever with severe vomiting, diarrhoea and bleeding. The outbreak is concentrated in North Kivu and Ituri provinces. There are some signs case numbers in the North Kivu city of Beni may be levelling off but WHO experts are cautious.

They say the apparent lull might be due to people gettingill but failing to seek proper diagnosis and treatment.

The West Africa Ebola outbreak Farrar referred to lasted for two years from 2014. It infected 28 000 and killed more than 11 300 people in an epidemic that devastated Sierra Leone, Liberia and Guinea and spread in sporadic cases to several other African countries as well as the United States and Europe.

The WHO says the risk of the disease spreading remains “very high” at national and regional levels and is working urgently with Congo and its neighbours – Uganda, Rwanda and South Sudan- to do everything to avoid that happening again.

WHO spokesperson Tarik Jasarevic said 25 million people have already been screened for Ebola at border checks with Congo’s neighbours. Vaccination campaigns have also begun for health workers in Uganda and South Sudan.

Jasarevic also said multiple threats to response teams’ ability to find, treat and prevent cases of Ebola infection makethe Congo situation particularly worrisome: “Gains could be lost if we suffer a period of prolonged insecurity,” he said.