The Ebola outbreak in the Democratic Republic of Congo is still growing and has a 70% chance of spreading into neighbouring South Sudan, new modelling has predicted.
Preparing for the deadly haemorrhagic fever to reach a country with some of the weakest healthcare in the world should now be a priority, researchers said.
The outbreak is centred in the Ituri province of Democratic Republic of Congo (DRC) but has already spread into Uganda and now has a 69.3% chance of reaching South Sudan, according to the peer-reviewed modelling in the Lancet medical journal.
Researchers found a far smaller chance of Ebola spreading to other neighbouring countries, with an 8.6% chance of getting to Rwanda and 2% of reaching Burundi.
The findings were published as the World Health Organisation (WHO) said the outbreak was still outpacing response efforts in the DRC.
Officials in DRC said the number of confirmed cases of the rare Bundibugyo strain had reached 1118, leading to 291 deaths.
WHO researchers modelled three scenarios of increasing severity for the Lancet paper and said the daily tally of cases and deaths was so far most closely tracking the medium scenario.
That would see around 8200 cases by September.
The researchers concluded: “Spillover is no longer hypothetical: as of June 22, 2026, DR Congo has 1048 confirmed cases and 267 deaths and Uganda has reported 20 confirmed cases, two confirmed deaths, and one probable death ... the estimated probability of importation into South Sudan remains 69.3%.”
France has this week seen an Ebola case – a doctor who returned from treating patients in DRC.
French authorities said the patient had been admitted to a specialist treatment facility and was in a stable condition, with the broader risk to the population described as low.
The virus is thought to have been spreading undetected for at least six weeks before an outbreak was formally declared mid-May.
A lack of testing kits that could detect the Bundibugyo strain meant health workers at first struggled to determine that an outbreak was underway.
There have also been early indications that the telltale haemorrhaging symptoms seen in the more common Zaire strain have been less frequent in this outbreak, making it easier for medics to confuse the signs with other diseases.
Long-running conflict in northeastern DRC has added to the difficulties of trying to stop the spread.
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