136 Deaths, Rare Ebola Strain, No Vaccine: Why The Bundibugyo Outbreak In Congo Is Proving Difficult To Contain

The ongoing Ebola outbreak in the Democratic Republic of the Congo (DRC) and Uganda has resulted in 136 deaths and over 530 suspected cases. On Tuesday, World Health Organisation chief Tedros Adhanom Ghebreyesus said he was "deeply concerned about the scale and speed of the epidemic" after declaring the outbreak an international emergency last week. Unlike most historical outbreaks in the DRC caused by the Zaire strain, genetic sequencing has confirmed that this outbreak is due to the rare Bundibugyo virus. As there are currently no approved therapeutics or vaccines specifically for the Bundibugyo virus, the WHO has classified this outbreak as an "extraordinary event."

Bundibugyo, a rare strain with no vaccine

The current Ebola outbreak in Congo is particularly concerning because it involves the Bundibugyo strain.

The Bundibugyo virus (BDBV) is one of the six known species within the Orthoebolavirus genus. It causes Bundibugyo virus disease (BVD), a severe and often fatal viral haemorrhagic fever. This is the third Bundibugyo outbreak, with case fatality rates in the previous two outbreaks ranging from 30% to 50%.

• First identification, 2007: The virus was discovered in late 2007 during an outbreak in the Bundibugyo District of western Uganda. That outbreak infected 149 people and killed 37.
• Second Outbreak, 2012: The virus re-emerged in the Isiro health zone of the Democratic Republic of the Congo (DRC), causing 52 cases and 29 deaths.
• Third Outbreak, 2026: The current May 2026 outbreak in the Congo and Uganda has been declared a Public Health Emergency of International Concern.

Also read: Bundibugyo Strain Of Ebola Virus Explained: The Rare Strain Responsible For The Current Outbreak

No vaccine

Currently, there are no approved vaccines, licensed therapeutics or monoclonal antibodies for the Bundibugyo strain, unlike the more common Zaire strain of Ebola.

Rapid escalation and high fatality

The outbreak is no longer contained within a single region and has already crossed the border into Uganda. WHO has also cautioned that the outbreak is probably more extensive than detected. "There are significant uncertainties regarding the true number of infected persons and geographic spread associated with this event at present. In addition, there is limited understanding of the epidemiological links with known or suspected cases," WHO mentioned.

Also read: Hantavirus To Ebola: Why Are Infectious Disease Outbreaks Rising Rapidly In 2026?

Healthcare workers at risk

There have been reports of at least four fatalities among healthcare professionals, signalling gaps in infection prevention and the potential for amplification within hospitals.

Humans catch the virus initially through direct contact with infected wildlife, including bats, monkeys, chimpanzees, or forest antelopes. The virus spreads rapidly through direct contact with the bodily fluids, like blood, vomit, faeces, saliva, or semen of an infected person or via contaminated surfaces such as bedding or clothing. Therefore, health and care workers are at a higher risk of getting infected.

An infected individual cannot transmit the disease before they have symptoms, and they remain infectious as long as their blood contains the virus.

Super-spreader events

Unsafe burial practices that involve direct contact with the dead body are a major driver of transmission. Poor infection prevention in healthcare facilities can also cause rapid amplification.

Vague symptoms that progress rapidly

Symptoms appear 2 to 21 days after exposure. Infected individuals are not contagious until they show physical symptoms.

Progression begins abruptly with flu-like signs, including sudden high fever, severe headache, intense fatigue, muscle/joint pain, and a sore throat.

As the disease attacks vital organs and blood vessels, it progresses to massive gastrointestinal issues like severe watery diarrhoea, persistent vomiting, abdominal pain, and a rash.

In fatal cases, internal and external bleeding occur, leading to metabolic shock and multi-organ failure.

Also read: US Pledges Major Ebola Aid Surge, Slams WHO Over Delayed Alert In Africa Outbreak

Is it a threat to India and rest of the world?

Ebola cannot spread like Covid-19 because it is not an airborne virus. It only spreads through direct contact with infectious bodily fluids. People infected with Covid-19 can spread the virus without feeling sick. Ebola patients only become contagious after they develop clear symptoms.

However, the outbreak is highly concerning.

Despite not being an airborne threat, international health agencies are highly alarmed by this specific epidemic primarily because there are no approved vaccines or specific drugs to fight this rare Bundibugyo strain. Additionally, the virus is moving through the eastern DRC and neighbouring border regions with a high fatality rate.

While the risk for other countries that do not share borders with DRC remains low, it is essential to stay vigilant. Many international airports have already reinstated health screenings and temperature checks for travellers arriving from East Africa to intercept potential cases early.

In India, the government has reviewed standard operating procedures for screening, surveillance, quarantine and case management, while laboratory preparedness is also being ramped up. The National Institute of Virology (NIV), Pune has been designated for Ebola testing, with additional laboratories expected to be onboarded in phases.

Disclaimer: This content including advice provides generic information only. It is in no way a substitute for a qualified medical opinion. Always consult a specialist or your own doctor for more information. NDTV does not claim responsibility for this information.