The Democratic Republic of the Congo has reported 5,290 confirmed Bundibugyo Ebola cases and 2,516 related deaths, with 837 patients hospitalised in isolation. Contact-tracing coverage stands at 82.9 per cent. In the most recent complete reporting week available, the outbreak recorded its highest weekly figures to date: 567 cases and 296 deaths.

Why the weekly peak matters more than the total

Cumulative totals only ever rise, so they say nothing about direction. The weekly figure does, and a record week three months into an outbreak is the clearest available signal that transmission has not been brought under control.

WHO’s assessment describes the outbreak as intensifying, with sustained transmission, expanding geographic spread and persistently high mortality. That is unusually direct language for the organisation, and it is worth reading as written rather than softened.

Ituri province remains by far the most affected, with cases reported from 28 of its 36 health zones — meaning the outbreak is distributed across most of a province of more than four million people rather than confined to a cluster.

The case that travelled, and what it showed

One detail from this outbreak deserves more attention than it received. A confirmed Bundibugyo case was reported in France in June, in someone who had deployed to support the response in the DRC.

The outcome is the informative part. The patient recovered and was discharged in July after two consecutive negative tests. No secondary transmission was identified. All five flight contacts, and those traced in the DRC, completed 21-day follow-up without developing symptoms. France reported no further cases in the 28 days after discharge.

That is what functioning containment looks like: one imported case, contacts identified and followed, no onward spread. It is also a reminder of what the DRC is being asked to do at a scale of thousands, with a fraction of the resources.

The malaria complication

A point raised by malaria specialists during this outbreak is worth setting out, because it is not obvious.

The DRC has very high malaria rates, and early malaria symptoms — fever, headache, aching muscles, fatigue — closely resemble early Ebola symptoms. In an outbreak zone, that produces two failure modes at once. People with malaria are treated as suspected Ebola cases and sent to isolation facilities where they may be exposed. And people with Ebola are assumed to have malaria and stay at home, infecting their household.

It also means routine malaria services frequently collapse during an epidemic response, which kills people through a disease nobody is counting in the outbreak figures.

What is being built

Five central African countries are strengthening cross-border surveillance, with the Central African Republic deploying a mobile laboratory near its borders. Patient enrolment has begun in a trial to identify the first effective treatments for this species, for which no licensed vaccine or therapy exists.

Neither will change the numbers this month. The figure that would is the contact-tracing percentage, and at 82.9 per cent roughly one identified contact in six is not being followed.

Sources

• ECDC — Ebola outbreak in the DRC and Uganda, case and death figures
• WHO Disease Outbreak News — Bundibugyo virus disease, DRC, including the imported case in France
• Bush Center global health update — malaria and the Ebola response