New Ebola cases in Congo: What you need to know

A new Ebola outbreak is circulating in the Democratic Republic of Congo. Genetic evidence suggests it had been spreading for weeks, possibly months, before detection. The strain is current, and much about its specific behavior remains unknown.

Understanding why the virus spreads as it does begins with how it enters the body. Unlike respiratory viruses that travel through air, Ebola requires something more direct.

How Ebola virus enters the body

The virus needs direct access through mucous membranes in the mouth, nose or eyes, or via cuts and wounds on skin. Intact skin provides a barrier, but any breach becomes an entry point.

David Heymann, an epidemiologist at the London School of Hygiene and Tropical Medicine who first studied Ebola in 1976, describes the transmission in practical terms: "The Ebola virus is spread from person to person by body fluids. So that means by blood, by saliva, possibly by feces, by urine, and also we now know in persons who are recovered through the semen." 

The virus targets these specific routes because they provide direct access. 

Infected people shed enormous amounts of virus in these fluids. 

Healthcare workers handling bodily secretions without protection face particular risk. 

Family members caring for sick relatives during late-stage illness, when the viral load peaks, are also highly vulnerable.

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What happens inside? A systemic attack

The virus doesn't attack randomly. 

Bodo Plachter, professor of virology at the University of Mainz in Germany, explains the mechanism: "The virus will always replicate at the site of entry in the lymph nodes, but then it spreads throughout the body and gets carried away by cells through the bloodstream to different organs." 

Critically, it targets the body's immune defenders first – the very cells designed to recognize and destroy invaders. Once disabled, the immune system is unable to fight back. 

The result is catastrophic: the viral load becomes enormous, and healthcare workers and family members face exposure to extraordinarily high concentrations of infectious material.

Symptoms: How the disease progresses 

Heymann, observing Ebola clinically and epidemiologically for decades, describes a disease that disguises itself. 

The early symptoms are almost indistinguishable from common illnesses. 

He explains: "The initial signs and symptoms are like any other minor disease, like a cold, an infection, even like malaria. Then, in some instances, people begin to feel better. After that, they then begin with a hemorrhagic disease where blood begins to ooze out from different body orifices." 

That apparent recovery is the trap. By the time the disease is unambiguously diagnosed, patients are at peak infectiousness. "The people who are most infectious are the people who have the most virus in the solution or the body fluid that infects. So, if there's blood contamination of a person who's dealing with a patient, that will be full of virus,” he says. 

This timing creates a critical vulnerability: healthcare workers and family members face the highest exposure precisely when the diagnosis becomes clear.

Why Ebola remains infectious after death

Death does not render the virus harmless. When someone dies from Ebola, their corpse contains high levels of viable virus. Bodily substances including blood, tissue fluid, and gut secretions remain present. The body therefore stays moist, especially in warm and humid climates.

Heymann describes what happens: "There's a ritual of cleaning the body and doing other things." 

"And that virus is present in the body secretions and solutions that people may come in contact with," he adds. "And usually, the body is still quite warm, and the virus is still living." 

The virus persists as long as it remains moist in bodily fluids.

On the molecular level, Plachter describes a virus as a complex structure of multiple macromolecules held together by moisture. "If somebody dies, there is enough fluid still available, so the virus is stable inside the body." 

This is why the timing of funeral practices matters. In parts of West Africa, families wash and handle bodies within days of death – the window when the virus remains most dangerous.

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What comes next in the disease outbreak

This outbreak is difficult to contain. People travelling across borders spread the virus to other countries, while customary burial practices involve contact with infectious corpses.

Heymann explains: "It will be very difficult to stop because of the mobility of people, because of the misunderstanding about burial and the violence that's occurring, because of civil war, and because of just lack of trust of the people in the area of outsiders."

The "misunderstanding about burial" is connected to specific practices. Safe approaches exist: gloves and masks, and the careful handling and washing of bodies. These require community acceptance and the involvement of local leadership.

History offers a counterpoint. In 1977, the second Ebola outbreak in Congo was contained when a doctor recognized it early and isolated the patient properly. No further cases occurred.

But the current situation is more complicated. The outbreak is occurring in areas with significant population movement and ongoing conflict. 

Research itself is constrained. The virus can only be studied safely in high-level biosafety laboratories, of which there are very few globally. For this outbreak strain, key questions remain unanswered.

Both experts point to what matters: early recognition, proper infection control, and community understanding. But in areas with mobility, conflict, and skepticism, achieving all three simultaneously could be extraordinarily difficult.