Following the recent hantavirus outbreak aboard a cruise ship, which renewed public concern around emerging infectious diseases, the ongoing Ebola outbreak in Central Africa has again placed outbreak preparedness, rapid diagnostics, and the risks of zoonotic spillover into sharp focus. Recent G7 discussions have also emphasized the need for coordinated financing to strengthen global health security and close critical gaps in outbreak response capacity.
As of July 3, 2026, a total of 1,481 confirmed Ebola cases, and 454 deaths, have been reported across the Democratic Republic of the Congo (DRC) and neighboring Uganda. Nearly 50 years after Ebola virus was first identified in 1976 near the Ebola River in DRC, the disease continues to challenge healthcare systems, public health agencies, and diagnostic laboratories.
While Ebola virus disease, or EVD, is not a new threat, the current outbreak underscores persistent gaps in surveillance systems, laboratory readiness, healthcare infrastructure, fiscal support, and coordinated international response capacity.
To explore the broader significance of the ongoing outbreak and its implications for global health preparedness, Today's Clinical Lab spoke with David A. Schwartz, MD, MS Hyg, FRSM, FCAP, a board-certified pathologist, medical epidemiologist, and internationally recognized expert with over four decades of experience in viral hemorrhagic fevers and maternal-fetal infectious diseases.
What is Ebola virus disease?
Ebola virus was first identified in 1976 in Sudan and DRC. It was named after the Ebola River, which was located near the epicenter of these initial cases. Classified under the genus Orthoebolavirus (formerly known as Ebolavirus) within the Filoviridae family, scientists have identified six distinct species of the virus. Among these, the Zaire species—the most lethal—has been responsible for the majority of the outbreaks in Africa. Two other prominent species are Sudan and Bundibugyo species.
How deadly is Ebola virus?
Between 1976 and 2022, there have been more than 40 Ebola outbreaks, leading to approximately 35,000 cases, and more than 15,000 deaths.
Historically, Ebola outbreaks have had fatality rates ranging from approximately 25–90%, depending on the viral species, healthcare and supportive care access, and availability.
The 2014–2016 West African epidemic (caused by Zaire species) was particularly devastating. The outbreak led to approximately 28,000 cases and over 11,000 deaths, underscoring the catastrophic impact of viral spread when outbreaks occur in densely populated areas with limited healthcare resources.
How is Ebola virus spread?
Ebola is a well-characterized zoonotic disease in which the virus resides in animal reservoirs, primarily African fruit bats, and “spills over” into human populations. Once introduced into humans, transmission occurs via direct contact with the blood or bodily fluids of an infected person, as well as through contact with contaminated surfaces or objects.
What are the symptoms of Ebola virus infections?
The incubation period for Ebola virus disease is quite broad, typically ranging from 2 to 21 days, with most patients developing symptoms within 8 to 10 days following exposure. Early-stage infection, which is also referred as “dry” symptoms, often begins abruptly with symptoms similar to other infectious diseases, including fever, severe headache, fatigue, chills, muscle pain, and malaise.
As the disease progresses, typically within the first week of illness, patients may develop “wet” gastrointestinal symptoms, such as nausea, vomiting, diarrhea, abdominal pain, and profound dehydration.
In severe cases, Ebola can cause liver and renal dysfunction, coagulation abnormalities, internal and external bleeding, shock, and multi-organ failure. Although hemorrhage has historically been associated with Ebola virus disease, bleeding manifestations occur in only a subset of patients and are not required for diagnosis.
Why the current Ebola outbreak matters
The ongoing EVD outbreak is of global concern because it is driven by the rare Bundibugyo ebolavirus species, for which there are no approved vaccines or treatments. The outbreak is spreading rapidly across Central Africa amid dense populations and ongoing geopolitical and humanitarian challenges, increasing the risk of sustained transmission.
According to Schwartz, one of the most concerning aspects of the current outbreak is that it involves a relatively understudied and genetically distinctive Ebola species. Bundibugyo virus has only been responsible for two previously documented outbreaks, giving scientists and clinicians far less experience compared with the more common Zaire ebolavirus, he says. This distinction has important implications for clinicians, researchers, and diagnostic laboratories.
“All of our recent experience, diagnostic development, and therapeutic advances have been centered on the Zaire strain,” Schwartz says. “We now have a major transnational outbreak caused by a species for which we have limited diagnostic capabilities, very little clinical experience, and no approved therapeutics.”
“The outbreak is also occurring under particularly difficult circumstances. Active conflict, population displacement, limited healthcare infrastructure, concurrent mpox activity, and reduced international funding have complicated response efforts,” he says.
Together, these factors have increased concerns among global health officials about outbreak containment and underscore the importance of maintaining robust preparedness capabilities before public health emergencies occur.
Current testing approaches for Ebola virus disease
Laboratory testing is essential for Ebola outbreak control because early symptoms are nonspecific and difficult to distinguish from other infectious diseases.
Current key diagnostic strategies used during Ebola outbreaks include the following:
Nucleic acid amplification tests (NAATs)
Reverse transcription polymerase chain reaction (RT-PCR) remains the gold standard for Ebola diagnosis. By detecting viral RNA in blood, serum, or other clinical specimens, RT-PCR can confirm active infection with high sensitivity and specificity. Due to its efficacy and accuracy, the WHO and the U.S. Centers for Disease Control and Prevention continue to recommend RT-PCR as the primary confirmatory test for suspected Ebola cases.
Rapid molecular assays
In outbreak settings, rapid molecular assays provide a faster alternative that can be deployed closer to the point of care. These NAATs are designed for use in field laboratories and resource-limited environments, facilitating quicker isolation and contact-tracing decisions.
Antigen detection tests
Rather than detecting viral genetic material, antigen detection assays (e.g., EBOLA Ag K-SeT) identify specific Ebola virus proteins present in patient samples.
Although generally less sensitive than molecular methods, antigen detection tests remain a valuable option for frontline screening due to their rapid turnaround times, often providing results within minutes and enabling the identification of probable cases in remote settings with limited laboratory infrastructure.
Though they are not a substitute for confirmatory molecular testing, rapid diagnostics can provide actionable information much faster than centralized laboratory testing and support timely public health interventions while definitive results are pending, Schwartz says.
Serology tests
Serology tests detect antibodies generated in response to infection and are primarily used to assess prior exposure and characterize population-level immunity. The delayed development of detectable antibodies limits the utility of serological testing for the early diagnosis of acute EVD, notes Schwartz. However, serological testing remains useful for retrospective epidemiological studies and outbreak investigations, providing insights into transmission dynamics and the broader patterns of disease spread.
Increased global travel, urbanization, ecological disruption, cross-border movement, and repeated zoonotic spillover events create opportunities for infectious diseases to spread beyond their traditional geographic boundaries.
istock, janiecbros
Current challenges in early Ebola virus disease detection and diagnosis
Effectively managing an Ebola outbreak requires overcoming a multifaceted set of diagnostic, operational, and logistical barriers that can delay critical patient identification and outbreak containment.
Five critical challenges to early Ebola virus detection in outbreak settings:
1. Overlapping symptoms of Ebola virus disease with other infectious and noninfectious diseases
One of the greatest challenges to early EVD detection is the lack of specific clinical signs that distinguish it from other infectious and noninfectious conditions. As Schwartz explains, “Ebola virus has a fairly significant asymptomatic period, during which it is not contagious. But once the symptoms begin, the symptoms are nonspecific and mimic several other tropical and infectious diseases.”
In the early febrile “dry” phase, Ebola symptoms may resemble malaria, dengue fever, typhoid, Lassa fever, or other viral hemorrhagic fevers like Marburg virus disease, while later “wet” gastrointestinal and hemorrhagic symptoms can overlap with conditions such as cholera and bacterial sepsis.
“In some rare presentations, [EVD] can also be clinically confused with noninfectious diseases, such as certain leukemias, thrombotic thrombocytopenic purpura, and even hemolytic uremic syndrome,” Schwartz says. “There is nothing specific about the symptomatology that allows us to be certain that's what we're dealing with in an outbreak situation.” Therefore, laboratory testing is essential for accurate diagnosis and outbreak control.
2. Limited availability and deployment of molecular diagnostics
The current outbreak is caused by Bundibugyo virus (BDBV), a rare Ebola species responsible for only two previously documented outbreaks. Consequently, much of the global Ebola diagnostic infrastructure has been developed around the more prevalent Zaire ebolavirus, potentially limiting the performance of diagnostic platforms to detect BDBV. A recent Nature article reported that during the current Bundibugyo outbreak, initial frontline testing struggled to identify the causative strain because testing platforms were optimized for Zaire ebolavirus. Species-specific multiplex testing was required to detect the BDBV species responsible for the current outbreak, underscoring the need for broader assay coverage and enhanced preparedness for less frequent or emerging Ebola virus species.
3. Biosafety, specimen handling, and transportation barriers
Even when testing is available, safe sample collection, handling, and transport present significant logistical challenges. Ebola is a highly lethal pathogen, requiring strict biosafety protocols to protect healthcare workers and laboratory personnel. “Any time you deal with an Ebola patient, you’re dealing with a potentially lethal infection that can be transmitted during patient care,” Schwartz notes. “Proper protection is essential for those caring for patients and performing diagnostic tests.”
In remote outbreak settings, maintaining specimen integrity during transport across fragmented supply chains remains a critical challenge. As Schwartz emphasizes, “Samples must be properly preserved so they can be tested accurately, but diagnostics facilities may be many hours—or even days—away from the outbreak site.” Limited electricity, poor transportation networks, and inadequate laboratory infrastructure can further complicate the diagnostic process.
4. Conflict and insecurity undermine Ebola surveillance and response
Early detection and outbreak response efforts are further complicated by ongoing insecurity in eastern DRC. “We're dealing with testing and treatment in conflict zones, which of course has its own set of challenges,” Schwartz says. Conflict can limit the ability of surveillance teams, healthcare workers, and emergency responders to safely access outbreak hotspots, while millions of internally displaced people live in overcrowded settlements with limited sanitation, hygiene, and healthcare access. These conditions delay specimen collection, transport, laboratory testing, and contact tracing, while simultaneously increasing transmission risks and making outbreak containment more difficult.
5. Gaps in Ebola treatments and vaccine coverage
The current outbreak highlights a major vulnerability in global health preparedness: the absence of approved therapeutics for the rare Bundibugyo virus (BDBV) species. While decades of research have produced highly effective monoclonal antibody therapies (e.g., Ebanga and Inmazeb) and vaccines (Ervebo and Zabdeno), these countermeasures are specifically targeted at the Zaire species rather than the currently circulating Bundibugyo virus species, Schwartz explains. As a result, clinicians managing BDBV infections have limited treatment options beyond supportive care, broad-spectrum antivirals, or investigational therapies.
Could Ebola virus disease become a global pandemic?
Ebola virus’s historically high case fatality rate has fueled considerable media attention around whether it could become a global pandemic. However, Ebola’s transmission differs significantly from SARS-CoV-2 and influenza. Unlike respiratory viruses, Ebola is not airborne and spreads primarily through direct contact with infected body fluids or contaminated materials. Additionally, infected individuals are generally not contagious during the incubation period and primarily only transmit the virus after symptom onset. These characteristics enable effective outbreak containment through contact tracing, targeted physical preventive measures, and timely patient management.
Nevertheless, experts, including Schwartz, caution against complacency. Increased global travel, urbanization, ecological disruption, cross-border movement, and repeated zoonotic spillover events create opportunities for infectious diseases to spread beyond their traditional geographic boundaries. Drawing on lessons from the COVID-19 pandemic and recent outbreaks—Mpox, Hantavirus, and Oropouche virus— Schwartz emphasizes that pathogens once considered geographically restricted or endemic can rapidly emerge in new and unexpected settings.
Lessons and priorities for Ebola virus preparedness
The current BDBV outbreak highlights the continued importance of surveillance, laboratory readiness, diagnostic innovation, and international collaboration.
However, the response has unfolded amid constrained global health resources, including fluctuating international funding for outbreak preparedness. WHO emergency operations often rely on rapid mobilization of resources to support field deployment, laboratory capacity, and workforce planning, while early response phases have also revealed shortages of essential supplies, including personal protective equipment.
In response to these challenges, recent G7 discussions have focused on coordinated international financing to address critical gaps in outbreak preparedness and control, including emergency assistance, vaccine deployment, laboratory strengthening, and broader health security initiatives. Parallel G20 discussions are expected to emphasize expanding access to molecular diagnostics, strengthening surveillance networks, and improving laboratory resilience in resource-limited settings.
When asked about key takeaways for laboratory leaders, Schwartz emphasized that “laboratories cannot afford to wait until outbreaks occur before developing diagnostic capabilities.” He addedthat “global travel has eliminated geographic borders, so any pathogen can surface anywhere in the world overnight.”
Beyond individual outbreaks, a “One Health” approach integrating medical, agricultural, and environmental expertise is increasingly recognized as essential to address emerging infectious threats at their source. Schwartz also stressed that preparedness depends on strong cross-sector collaborations, noting that private-sector partnerships are “not just critical but essential” for providing specialized expertise and operational capacity.
Nearly 50 years after Ebola was first identified, advances in diagnostics, surveillance, vaccines, and outbreak response have transformed global health preparedness. Yet the 2026 Bundibugyo outbreak shows that vulnerabilities remain when health systems are underprepared and pathogens are poorly understood. Even if contained, the outbreak reinforces the need to shift from a response-focused model toward stronger systems capable of detecting and containing threats early.
