Two vaccines against the Bundibugyo virus enter clinical trials in DRC

Authoritative sources in the Democratic Republic of Congo (DRC) have reported that the Ebola outbreak, declared on May 15, has exceeded 10,000 confirmed cases, including 4,887 deaths.

According to the latest report from the DRC's National Institute of Public Health (INSP), which contains data as of October 25, 10,060 confirmed cases have been recorded, with the fatality rate reaching 48.6%. To date, 2,684 infected individuals have recovered, and contact tracing coverage stands at 81.6%.

The most affected provinces in the eastern part of the country are Ituri and North Kivu, where 32 and 58 new cases were registered in the last 24 hours, respectively.

In total, the epidemic affects eight out of the 26 provinces of the DRC: Ituri and North Kivu, as well as Tshopo (north-central), Bas-Uele (north), Haut-Uele (northeast), South Kivu (east), South Ubangi (northwest), and North Ubangi (north).

This surge, which is the second deadliest and most contagious in world history, has already surpassed the scale of the outbreak in the same Congolese region between 2018 and 2020. Nevertheless, it still falls short of the most severe outbreak that occurred in West Africa between 2014 and 2016, which resulted in approximately 11,000 deaths and 28,000 infections.

The Bundibugyo strain causing the current epidemic has no specific treatment. However, the World Health Organization (WHO) is working on two vaccines that have passed phase one human trials and currently demonstrate safety, although their development may take several months.

Meanwhile, the DRC began an Ebola immunization campaign at the end of August, using the Ervebo vaccine, which is the only one available in large quantities. Although this vaccine was initially developed for the Zaire variant, which is more common, it has shown promising results against the Bundibugyo variant in animals.

The WHO also announced last Friday the start of clinical trials in the DRC to assess various potential vaccines against this strain. The Ebola virus is transmitted through direct contact with the bodily fluids of infected people or animals and causes severe hemorrhagic fever, accompanied by vomiting, diarrhea, and internal bleeding.

According to data from the United Nations, 9,552 confirmed cases of hemorrhagic fever Ebola have been recorded in the Democratic Republic of Congo, with the death toll exceeding 4,600. Over the last three weeks, the number of cases has increased by more than a thousand, and the number of victims by five hundred, while maintaining a fatality rate above 48 percent.

The infection has spread to the eighth province of Congo—North Ubangi, located on the border with the Central African Republic.

Furthermore, Ebola fever has been detected in Kenya, where this disease had not previously been recorded; nine cases and one death have been registered there, and 135 contacts are under observation.

In Nigeria, one case of the illness was recorded in a woman who arrived in Abuja from Uganda. Tests confirmed the presence of the same virus strain as in Congo. Consequently, more than 40 close contacts have been identified.

It should be noted that the outbreak in Uganda was declared over at the end of July after 20 cases were registered, including two fatalities.

In the eastern part of the Democratic Republic of Congo (DRC), a large-scale clinical trial of vaccines designed to combat the Bundibugyo Ebola virus began on Friday. The first participants were vaccinated in the country that is battling the largest registered outbreak of this virus.

The Phase 2/3 trial, named Tumaini, was launched in Bunia, the capital of the most affected province of Ituri. The research is funded and supported by the Coalition for Epidemic Preparedness Innovations.

This situation unfolds against the backdrop of an escalating Ebola crisis, which has claimed over 4,600 lives in the DRC since May. Despite the scale of the outbreak, no vaccine specifically developed against the Bundibugyo virus has been approved yet.

Tumaini, which translates to 'hope' in Swahili, aims to assess the safety, immune response, and efficacy of several vaccine candidates. Special attention is paid to people who have been in contact with confirmed Ebola patients and are at high risk of infection.

The study uses an adaptive platform design, allowing multiple vaccine candidates to be evaluated within a single study through a ring vaccination approach targeting contacts of confirmed cases.

The first vaccine included in the trial is Ervebo. This vaccine already has a license to prevent diseases caused by the Zaire ebolavirus, but its effectiveness against the Bundibugyo virus has not yet been proven.

Two more vaccines specifically developed against the Bundibugyo virus are expected to join the trial soon: one developed by Moderna, and the other by Oxford University in collaboration with the Serum Institute of India.

Chike Ikechewazu, Executive Director of the World Health Organization's Emergency Programme, noted that the launch of the Tumaini trial is a critical step in determining the ability of candidate vaccines to effectively protect people from the Bundibugyo virus.

WHO Regional Director for Africa, Mohamed Janabi, also welcomed the start of the trial on Friday. He emphasized that the study will provide vital data on candidate vaccines while strengthening the response to the current outbreak and preparedness for future epidemics.

According to the latest data published Wednesday by local DRC health authorities, 9,704 confirmed cases of Ebola, including 4,687 deaths, were recorded as of October 20, corresponding to a fatality rate of 48.3%.

The epidemic was declared in the DRC on May 15, and two days later, the WHO classified it as a public health emergency of international concern. Subsequently, the African Centre for Disease Control and Prevention declared it a continental security emergency.

The current Ebola outbreak is the largest and deadliest in the history of the DRC and the second-largest Ebola outbreak in the world after the West Africa epidemic during 2014–2016.