Faster diagnostics, deeper insights: Researchers strengthen response to Ebola outbreaks
Two studies on the 2026 Bundibugyo virus outbreak highlight new approaches to rapid diagnostics and vaccine preparedness
Colorized transmission electron micrograph of an Ebola virus virion.
The current outbreak of Bundibugyo virus (BDBV) in the Democratic Republic of the Congo highlights the challenges of responding to rare but potentially devastating infectious diseases. Two studies led by researchers from the German Center for Infection Research (DZIF) at Charité – Universitätsmedizin Berlin and the German Primate Center – Leibniz Institute for Primate Research in Göttingen, together with other national and international collaborators, now provide important insights for outbreak response. One demonstrates how diagnostic tests can be evaluated rapidly during an outbreak; the other investigates the biological properties of the 2026 BDBV strain and whether an existing Ebola vaccine could offer some cross-protection. Both studies were published this month in The Lancet Infectious Diseases.
Rapid evaluation of diagnostic tests
During the COVID-19 pandemic, a research team at Charité – Universitätsmedizin Berlin led by Prof. Christian Drosten, a DZIF scientist, rapidly developed a PCR test for SARS-CoV-2 and made it publicly available within a short time. Because the assay’s performance had already been verified, manufacturers could replicate it and bring it to market quickly, enabling widespread testing from the first wave onwards. Since then, the EU has tightened regulations for new diagnostics, with each new test requiring its own validation study. This can slow the deployment of diagnostics during outbreaks.
The 2026 BDBV outbreak exposed this challenge. BDBV can cause severe hemorrhagic disease, but unlike Ebola virus, there are currently no licensed vaccines or therapeutics specifically targeting it. The available certified Ebola test was not designed to detect BDBV, while no outbreak-strain virus isolate was initially available for test validation. On May 20, 2026, Charité admitted a US patient who had contracted BDBV in the Democratic Republic of the Congo. From a throat swab, researchers led by Drosten isolated the virus’s genetic material and developed a reference standard—a benchmark that diagnostic tests can be assessed against.
The team then assembled an international network of nine laboratories, including members of DZIF, the German National University Medicine Network (NUM), and several European research consortia and encompassing major university hospitals and high-containment BSL-4 facilities. The network evaluated four candidate PCR tests from two manufacturers. Within two weeks, the tests underwent comprehensive analytical and clinical assessment, with no evidence of cross-reactivity. The study demonstrates that a decentralized network can provide robust performance data rapidly, potentially helping to accelerate regulatory approval and availability of diagnostic tests during outbreaks.
The findings also highlight the need for close collaboration between public research institutions and diagnostic companies. Public funding could help accelerate the regulatory evaluation of diagnostic tests for rare, high-consequence pathogens, where commercial incentives are limited, says Drosten.
Insights into the 2026 Bundibugyo virus and potential vaccine cross-protection
The second study, led by DZIF scientist Prof. Stefan Pöhlmann at the German Primate Center (DPZ) in Göttingen, examined whether genetic differences in the glycoprotein of the 2026 BDBV strain might alter its ability to enter human cells. The glycoprotein is the virus’s most important surface protein and the key factor in its infectivity. Because work with authentic BDBV requires biosafety level-4 containment, the researchers used pseudovirus particles carrying the glycoproteins of BDBV strains from 2007–08, 2012 and 2026. They found no evidence that the 2026 virus enters human cells more efficiently than earlier variants.
The researchers also investigated whether vaccination against Ebola virus could generate antibodies capable of neutralizing BDBV. Serum samples from ten healthy volunteers who had received the licensed recombinant VSV-ZEBOV Ebola vaccine were analyzed before vaccination and 28 and 180 days afterwards. Following vaccination, antibodies from the participants were able to neutralize pseudoviruses carrying the glycoproteins of all three BDBV strains, including the 2026 strain. BDBV-specific neutralization was detected in six of ten vaccine recipients at both time points, although neutralizing activity was around 3.5 to 3.6 times lower than against Ebola virus.
The findings suggest that the licensed Ebola vaccine may provide some degree of cross-protection against BDBV and are consistent with previous studies in non-human primates. However, the current study used pseudovirus particles in vitro. The findings therefore require confirmation with authentic BDBV and do not demonstrate that vaccination protects people against BDBV infection or disease.
Strengthening outbreak preparedness
Together, the studies show how rapid diagnostic evaluation, virological research and immunological analyses can complement each other during an emerging outbreak. Establishing international laboratory networks, reference materials and regulatory pathways in advance could help shorten the time from outbreak detection to reliable diagnostics and potential preventive measures.
Source: Press release of Charité – Universitätsmedizin Berlin
