The Ebola outbreak unfolding in the Democratic Republic of Congo has triggered urgent international concern, with health officials racing to slow its spread. The World Health Organization confirmed Wednesday that nearly 600 suspected cases and 139 deaths have now been linked to the crisis, and warned that those numbers are likely to climb in the days ahead.

“We expect those numbers to keep increasing given the amount of time the virus was circulating before the outbreak was detected,” WHO Director General Tedros Adhanom Ghebreyesus said during a press briefing. The WHO has labeled the situation a public health emergency of international concern, though it has stopped short of calling it a pandemic.

This particular outbreak, caused by the lesser-known Bundibugyo virus, has prompted heightened alarm because there are currently no approved vaccines or treatments specifically for this strain. Here’s a clear breakdown of what’s happening, how Ebola spreads, and what global health officials are doing in response.

What Is Ebola and How Does It Spread?

Ebola is a severe, often deadly illness that affects both humans and other primates. The virus belongs to a family known as orthoebolaviruses, with six identified types — three of which have caused major outbreaks. Fruit bats are believed to be the natural reservoir hosts.

The disease typically spreads through:

• Direct contact with blood, bodily fluids, or organs of an infected person or animal
• Contaminated surfaces such as bedding, clothing, or medical equipment
• Caregiving environments where protective measures are weak
• Unsafe burial practices involving handling of the deceased

Importantly, an infected person cannot transmit the virus until they begin showing symptoms. Once infected, they remain contagious as long as the virus is present in their blood.

Symptoms and Incubation Period

The incubation period ranges from 2 to 21 days. Early symptoms can look deceptively like more common illnesses, including:

• Fever
• Headaches
• Sore throat
• Fatigue

As the disease progresses, patients may experience vomiting, diarrhea, abdominal pain, and a rash. In more severe cases, Ebola can lead to internal or external bleeding and damage to the central nervous system. The Bundibugyo strain has a fatality rate estimated between 25% and 50%.

Where the Outbreak Stands Now

According to WHO data updated through May 20:

• Democratic Republic of Congo: Around 600 suspected cases, 33 confirmed, and 139 deaths
• Uganda: 2 confirmed cases and 1 death linked to the outbreak

American physician Peter Stafford, who was working as a surgeon in the affected region, has since been evacuated to Germany along with six other U.S. nationals classified as high-risk contacts. The U.S. Centers for Disease Control and Prevention has confirmed that no suspected or probable cases have been reported in the United States, and the overall risk to Americans remains low.

How the Outbreak Began

The WHO suspects the outbreak originated in Mongbwalu, a mining hub in Ituri province in Congo. From there, the virus is believed to have spread as people traveled to seek medical attention. Investigators are still piecing together the timeline.

A suspected Ebola-related death was recorded on April 20, but the situation escalated sharply on May 5 with what officials describe as a “super-spreading event.” Reports of additional deaths surfaced through social media before authorities were able to formally confirm the outbreak.

The Bundibugyo strain was officially identified on Friday, the same day Congo and Uganda jointly confirmed an Ebola outbreak. Uganda noted that its first case had been imported from Congo.

Demographic data suggests most patients are between 20 and 39 years old, and more than 60% are women — a pattern indicating likely spread within households and among caregivers.

Why This Outbreak Is Especially Hard to Contain

This marks the 17th Ebola outbreak in Congo since the virus was first identified in 1976. While Congo has decades of experience battling the disease, several converging factors are making this outbreak particularly challenging:

• The affected region of Ituri is conflict-prone and difficult to access
• Highly mobile populations move frequently between mining areas
• Early symptoms resemble those of malaria and typhoid, delaying diagnosis
• Some lab tests had been calibrated for a different Ebola strain
• Global health organizations have faced funding cuts and operational instability

Despite the obstacles, officials credit Congo’s health authorities for acting quickly once the virus was identified. Lab results, for instance, were available within 16 hours of testing — a notable achievement in such a complex environment.

Comparing It to Past Outbreaks

Congo’s most recent previous outbreak, from September to December last year, resulted in 64 cases and 45 deaths, reflecting a steep 70% fatality rate.

However, the most devastating Ebola crisis on record began in Guinea in 2014. It spread to Sierra Leone, Liberia, and seven additional countries — including the U.S. and parts of Europe — and was eventually declared over in 2016. By that point, more than 28,600 people had been infected and over 11,300 had died.

Vaccines and Treatments: What’s Available?

Approved vaccines and antibody-based treatments exist for another Ebola strain — but not for the Bundibugyo virus currently driving this outbreak. The WHO has pledged to accelerate research into possible medical countermeasures.

According to Vasee Moorthy, senior adviser on research and development at WHO:

• A Bundibugyo-specific vaccine is in development but not yet ready for clinical trials. Estimated timeline: 6 to 9 months.
• Another candidate vaccine being developed in Britain and India could potentially be ready for trial within 2 to 3 months, though that timeline is uncertain.

In the meantime, supportive care — including hydration, infection control, contact tracing, safe burial practices, and community engagement — remains the most reliable approach to reducing mortality and slowing transmission.

Travel Restrictions and Global Response

The United States has tightened its border health protocols. Non-U.S. passport holders who have been to Congo, Uganda, or South Sudan within the past 21 days now face restricted entry. The screening measures, enacted under a Title 42 order, can remain in effect for up to 30 days.

The U.S. is also working with airlines and port-of-entry officials to monitor travelers and identify any who may have been exposed.

The Road Ahead

While the situation remains serious, health authorities stress that Ebola outbreaks have been successfully contained before — even in difficult environments. The combination of rapid testing, public awareness, vaccine research, and global coordination will determine how quickly this new chapter of the Ebola story can be closed.

For now, the focus remains on slowing transmission, protecting health workers, and supporting the communities at the heart of the crisis.