AREBO/BUDSEV: strengthening the diagnostic toolkit against Bundibugyo

AREBO is a project led by the Institut Bouisson Bertrand, under the supervision of Éric Delaporte, and by the National Institute for Biomedical Research (INRB) in the Democratic Republic of the Congo (DRC). It was designed in response to the ongoing Bundibugyo virus (BDBV) outbreak, with the aim of providing a rapid response to diagnostic needs in the field and sustainably strengthening diagnostic capacity in the DRC, both in central laboratories in Kinshasa and in decentralised laboratories. AREBO's primary aim is to strengthen the diagnostic toolkit available for BDBV, with an initial focus on molecular tests. In particular, the project is involved in the evaluation of commercial 'point-of-care' molecular tests, including those specifically adapted to BDBV or those covering filoviruses more broadly, for example on platforms such as GeneXpert, RADIONE or equivalent. These tests are evaluated using a reference panel to determine their performance, particularly in terms of sensitivity and specificity, and to assess their suitability for operational deployment in the field. Finally, a second focus of the project centres on the development and provision of serological tests to detect antibodies specific to various Ebola viruses, including BDBV. These tools should, in particular, enable the spread of the infection to be better documented, the immune response to be studied, and contribute to the monitoring and characterisation of those who have survived the infection. A serological study, the BUDSEV study, using the tests developed as part of the project, has begun in Ituri, one of the main hotspots of the BDBV epidemic. It aims, in particular, to determine whether vaccination with Ervebo® can induce cross-protection against BDBV, by comparing the immune responses observed in vaccinated and unvaccinated individuals, particularly among survivors of BDBV infection, suspected cases, and healthcare and frontline workers. Launched on 31 August 2026, the BUDSEV study covers three health zones in Ituri (Bunia, Nizi and Rwampara) and targets a sample size of 540 participants over a two-month period. The results will provide a better understanding of whether Ervebo®, originally developed against the Zaire Ebola virus, can also confer a certain level of protection against BDBV.