"The current ebola outbreak is notable because it’s caused by the Bundibugyo virus, a much rarer type of ebola for which we don’t have a widely used vaccine.

Unlike Zaire ebolavirus, the strain responsible for most large, high-profile outbreaks, Bundibugyo has historically been much less common.

UniSC developed a rapid test for Zaire ebola and I’ve taught about Zaire outbreaks in my viral pathogenesis lecture, focusing on the 2014–2016 West African epidemic, which resulted in about 28,000 cases and 11,000 deaths across Guinea, Sierra Leone and Liberia.

Zaire ebolavirus, in particular, has very high case fatality rates (sometimes up to 90%). Because of this, Zaire became the primary focus of vaccine development.

A highly effective vaccine (rVSV-ZEBOV/Ervebo) was first deployed during the 2018–2020 DRC outbreak and officially approved in 2019. Since then, Zaire outbreaks have been much better controlled and are typically contained more quickly, often remaining localised rather than escalating into the major crises seen in the past.

Bundibugyo virus, on the other hand, has historically caused only a couple of relatively small outbreaks (fewer than 120 cases combined) and tends to be less deadly, with case fatality rates around 30–40%. It has not previously been associated with large, multi-country epidemics on the scale seen with Zaire ebolavirus.

So this outbreak is unusual: it involves a strain that is both less studied and not covered by current vaccines, but is now causing a larger event than typically seen for Bundibugyo. Without a targeted vaccine, controlling its spread is likely to be more challenging."

"The World Health Organization (WHO) has declared an Ebolavirus outbreak in the Democratic Republic of the Congo (DRC) and Uganda a public health emergency of international concern. This outbreak is of concern due to the large number of suspected cases and deaths being reported. As of May 16, there are eight confirmed Bundibugyo virus cases, with an additional 246 suspected cases and 80 suspected deaths, including healthcare workers.

Bundibugyo virus, first identified in 2007 in Uganda (37 cases, 25% fatality) and then again in 2012 in the DRC (57 cases, 51% fatality), currently has no approved vaccines or treatments, though some vaccine candidates are in development. This is due to the small number of outbreaks with the virus compared to other strains of Ebolavirus.

Both Uganda and the DRC have experienced multiple Ebolavirus events previously. Testing and population movement restrictions will be implemented by health officials, along with WHO and other international partners, with the aim of containing the outbreak, identifying new cases, and providing emergency health care.

The outbreak is geographically widespread in both countries, with most cases reported from the remote eastern region of the DRC. This area has poor road networks, which will make accessing it by response workers difficult."

"The WHO declaration is scientifically justified, but it should not be read as a reason for public panic. Ebola does not spread like COVID-19 or influenza. It usually requires direct contact with blood, body fluids, contaminated materials, or unsafe healthcare and burial practices. This means Ebola outbreaks can be controlled, but only if the response is early, coordinated and trusted by communities.

What makes this outbreak important is that it involves Bundibugyo virus, a rarer member of the ebolavirus family. Most of the vaccines and antibody treatments we commonly associate with Ebola were developed for Zaire ebolavirus, not Bundibugyo virus. At best, a Zaire-based vaccine may provide limited or partial cross-reactive immunity, but in practical outbreak control, we should not assume reliable protection unless this is proven. This is why a Bundibugyo-specific vaccine, or ideally a broader pan-ebolavirus vaccine, is likely needed.

The warning signs are clear. Suspected undetected transmission, spread across borders, and infections or deaths among healthcare workers. When healthcare workers are affected, the health system itself becomes vulnerable, and that can accelerate an outbreak.

The priorities now are straightforward. This includes rapid diagnosis, safe isolation, contact tracing, strong infection prevention in hospitals, safe and dignified burials, and honest communication with communities. For countries outside the affected region, including Australia and Southeast Asia, the immediate risk remains low, but preparedness still matters. This is not about border closures or fear. It is about supporting affected countries quickly and using evidence-based public health before the outbreak becomes harder to contain."

"The Director-General of the World Health Organization has determined that the Ebola disease outbreak caused by the Bundibugyo virus in the Democratic Republic of Congo and Uganda constitutes a public health emergency of international concern, or PHEIC.

This is a formal determination under the International Health Regulations, the legally binding international framework for preventing and responding to the international spread of disease.

A PHEIC means the event is extraordinary, poses a public health risk to other countries through international spread, and may require a coordinated international response.

Determining an event to be a PHEIC sends an important international alert, and enables the WHO to issue temporary recommendations to governments and others on how to prevent or reduce international spread, while minimising unnecessary interference with international travel and trade. The WHO has begun the process to do this.

In the meantime, the WHO has issued advice to DRC and Uganda, to neighbouring countries with land borders adjoining affected states, and to all other states parties.

It is also important that the Director-General has determined that the higher level of ‘pandemic emergency’ has not been met. This category was introduced through amendments to the International Health Regulations adopted in 2024, following lessons from COVID-19.

A pandemic emergency requires additional criteria to be met, including high risk of wide geographical spread, pressure on health systems, and substantial social or economic disruption, and the need for rapid, equitable and enhanced international action across government and society."

"The World Health Organization (WHO) has declared an Ebolavirus outbreak in the Democratic Republic of the Congo (DRC) and Uganda a public health emergency of international concern. This outbreak is of concern due to the large number of suspected cases and deaths being reported; As of May 16, there are eight confirmed Bundibugyo virus cases, with an additional 246 suspected cases and 80 suspected deaths, including healthcare workers.

Bundibugyo virus, first identified in 2007 in Uganda (37 cases, 25% fatality) and then again in 2012 in the DRC (57 cases, 51% fatality), currently has no approved vaccines or treatments, though some vaccine candidates are in development. This is due to the small number of outbreaks with the virus compared to other strains of Ebolavirus.

Both Uganda and the DRC have experienced multiple Ebolavirus events previously. Testing and population movement restrictions will be implemented by health officials, along with WHO and other international partners, with the aim of containing the outbreak, identifying new cases, and providing emergency health care.

The outbreak is geographically widespread in both countries with most cases reported from the remote eastern region of the DRC. This area has poor road networks which will make accessing it by response workers difficult."

"The current situation with Ebola, caused by the Bundibugyo strain of ebolavirus predominantly in the Democratic Republic of Congo, is certainly one that warrants careful attention and makes the declaration of a public health emergency of international concern (PHEIC) very reasonable. However there are important points of clarification.

Firstly, a public health emergency of international concern is not at all related to there being concern of pandemic potential. Ebola is not a new virus, discovered in the late 1970’s and requires close contact or contact with blood or body fluid to be transmitted.

The mortality is much greater than that of respiratory viruses such as COVID-19, typically with the mortality of the Bundibugyo strain often quoted as between 25 to 50%. While this is bad for those infected and makes the current situation very significant, it does mean cases are more likely to be displaying significant symptoms and therefore be identified and ideally managed accordingly to limit onward spread. Provided, of course, that there are appropriate resources to do so, which hopefully the declaration of the PHEIC will help ensure is the case.

Concerning elements of the current situation include the high numbers of suspected cases and deaths have already been reported at approximately 250 to 300 and at least 88, respectively. It is thought, however, that the true numbers may already be far greater.

While there are vaccines for Ebola, unfortunately, these are for a different strain, namely, for Zaire ebolavirus. This means there are no vaccines or treatments for the Bundibugyo strain.

Suspected cases have been found in densely populated areas; there have also been suspected healthcare worker cases and spread across borders to Uganda. It is for these, and many other reasons, that the PHEIC has been declared. Hopefully, this will facilitate international coordination and cooperation to understand the true extent of the current outbreak, to coordinate surveillance as well as prevention and response efforts. With a coordinated response that can be facilitated by the declaration of the PHEIC, it is very reasonable to expect this current outbreak will be able to be geographically restricted, hence the global risk outside the region remains low."

"The declaration by the World Health Organization (WHO) of the current Ebola outbreak in DR Congo and Uganda as a public health emergency of international concern suggests the potential of the virus to be a global health threat. What makes it more serious is that the current outbreak is fuelled by an uncommon, but lethal strain of the virus (Bundibugyo) that has no approved vaccines or therapeutics.

The Africa CDC and WHO have reported more than 246 suspected cases, 80 suspected deaths, and eight laboratory confirmed cases in the DRC conflict, Ituri province.  This underscores a lag in detection: the virus has been spreading undetected for weeks, and given the high levels of people movement in that region due to mining activity and insecurity, this would explain the rapid spread.

Despite DR Congo having grappled with Ebola outbreaks in past, standard containment measures, such as contact tracing, isolation and proper burial practices, are currently hampered by regional insecurity. The current public health priority should focus on ensuring the immediate deployment of infection control supplies to frontline health facilities and to kick-start research into Bundibugyo-strain-specific interventions before the outbreak reaches a point at which it can no longer be contained.

Also, regional collaboration among the affected countries and donor agencies is critical at this stage.  This outbreak continues to highlight that in the Ebola-endemic region, continuous surveillance is critical for early detection and containment, and at the same time, non-biological factors, such as insecurity, can undermine the gains made in previous outbreaks."

"The WHO's declaration of the Bundibugyo virus disease outbreak in the Democratic Republic of the Congo and Uganda as a Public Health Emergency of International Concern demands an urgent, coordinated global response, one that places communities and their extensive local knowledge at its core.

The healthcare worker deaths raise serious concerns about gaps in infection prevention and control (IPC) and the potential for amplification within health facilities, leading to the wider community.

Strengthening IPC is critical, but cannot be achieved through top-down directives alone. Local health workers, traditional healers, and community caregivers carry deep contextual knowledge of how illness presents, spreads, and is understood within their communities.

This knowledge is not supplementary; it is foundational. IPC guidance and outbreak response strategies must be co-designed with community leaders, not simply delivered to them.

The international community must fund the response, ensure uninterrupted PPE supplies, and invest in local health systems and fair remuneration for health workers, professional and lay.

Risk to Australia and International Travellers:

Two confirmed cases have already been reported in Kampala following travel from the DRC, demonstrating the virus's capacity for international spread.

While Australia's direct risk remains low, travellers to affected regions should monitor WHO advisories, avoid contact with suspected cases, and seek immediate medical attention if symptoms develop post-travel.

The most effective protection is avoiding travel to active outbreak zones. Hand hygiene is one small component of a much broader, layered infection prevention strategy, including respiratory and mucous membrane protection."

"With respect to the Current Ebola outbreak in Africa, there are three things that deserve attention.

Firstly, the two confirmed cases in Kampala have no known connection to each other. That is often a warning sign that the outbreak in the DRC is larger than health authorities can currently see.

Secondly, at least four healthcare workers have died from Ebola virus. Previous Ebola epidemics have shown how easily health facilities can become major sites of transmission. The main problem is understaffed and under-resourced frontline care, combined with delayed presentation through informal clinics, pharmacies and traditional healers outside the formal health system.

Finally,  research into vaccines for Bundibugyo remains in pre-clinical stages. There is ongoing work on a pan-filo virus vaccine that could potentially have applications for Bundibugyo, but clinical-stage candidates do not yet exist. This underscores why preparedness planning and regulatory groundwork are essential now.

This outbreak is also a reminder of why the WHO matters. Epidemics like Ebola do not stop at borders, and no single country can coordinate surveillance, diagnostics, regulatory approvals and cross-border preparedness alone. Much of that unglamorous but essential work sits quietly inside the WHO system until a crisis like this exposes how important it really is."

"The World Health Organization (WHO) has declared the Ebola outbreak in the Democratic Republic of Congo (DRC) a Public Health Emergency of International Concern (PHEIC). This decision was mainly driven by the high fatality rate associated with Ebola and the significant risk of further spread under the current conditions in the DRC. At least 88 deaths have been reported so far, and the number is likely to increase in the coming days.

Ebola is one of the world’s deadliest infectious diseases, with several strains causing severe outbreaks, particularly the Zaire strain. Historically, most major Ebola outbreaks have been caused by the Zaire strain, which is associated with the highest fatality rates and was responsible for the largest outbreak in West Africa in 2014–2016. However, the current outbreak involves the Bundibugyo strain, raising major concerns because the widely used Ervebo vaccine is not effective against it. There are currently no approved vaccines or specific treatments for the Bundibugyo strain.

Ebola spreads through direct contact with infected bodily fluids. It is highly infectious, but is not as easily transmissible as measles or other respiratory infections. However, the risk of further spread in the DRC remains high due to social, economic, and political instability in affected areas. By declaring a PHEIC, WHO aims to strengthen international coordination, accelerate emergency response measures, and mobilise additional healthcare resources and support for affected regions.

Healthcare workers treating Ebola cases particularly require strict infection control protection, including adequate personal protective equipment (e.g. full-body suits, respirators, gloves, etc.), as they were disproportionately infected and killed during previous Ebola outbreaks. Community education and engagement are also necessary to control the outbreak early."

"I was professionally distressed to learn of this development over the weekend, because it means more eye inflammation and potential blindness down the track. I am an ophthalmologist (=eye surgeon) who works in the area of eye inflammation and infection. From the 2014-2016 West African outbreak, we know that up to one-third of Ebola survivors develop severe inflammation inside the eye (the condition ophthalmologists call ‘uveitis’), because the virus persists inside the eye after the infected person recovers from acute Ebola. This severe inflammation can be complicated by cataract. Eyes are frequently blinded by uveitis or its complications. It is the eye’s unique cellular and immune environment that facilitates the persistence of the virus and inflammation inside."

"The most important action required at this stage is to stand-up large-scale Bundibugyo-specific diagnostics in DRC, Uganda, and all surrounding African nations so that cases can be identified in people with mild symptoms to reduce spread and enable early intervention to reduce the death rates.

Effective diagnostics are essential to identify cases that can be isolated and treated. This outbreak is an example of the importance of maintaining global diagnostic capabilities, including public health units that can deliver diagnostics, and also utilising technology to ensure rapid design and production of tests. Globally, funding for diagnostic development is limited between outbreaks of disease, but then we are reminded each time situations like this arise that we need consistent efforts and funding for diagnostic development so that we can be prepared."