A mysterious disease with Ebola-like symptoms has emerged in the Democratic Republic of the Congo. According to the World Health Organization, the disease was first detected on January 21, and since then over 1,000 people have been infected and 60 people have died in the northwest of the country. Health officials are yet to determine the cause of the disease.
Initial investigations suggest the outbreak began in the village of Boloko, where three children died within days of eating the carcass of a bat. The symptoms of the infected include fever, headache, diarrhea, nosebleeds, vomiting blood, and general bleeding—matching those caused by viruses such as Ebola and Marburg. However, experts have ruled out these pathogens after testing more than a dozen samples from suspected cases.
In early February, health authorities recorded a second cluster of cases and deaths in the village of Bomate, several hundred kilometers away. There is currently no known link between the clusters. In most of the fatal cases, the interval between the onset of symptoms and death was only 48 hours.
In response to the second cluster of cases, a national rapid response team, including WHO health emergency experts, has been despatched from DRC’s capital, Kinshasa, to Equateur, the northwestern province housing Bomate. “Experts are stepping up disease surveillance, conducting interviews with community members to understand the background, and providing treatment for diseases such as malaria, typhoid fever, and meningitis,” the WHO said in its February 27 update on the outbreak.
Samples from 18 cases have been sent to the National Institute for Biomedical Research in Kinshasa, testing negative for the most common pathogens linked to hemorrhagic fever symptoms, although some tested positive for malaria, which isn’t unusual for the region.
“The exact cause remains unknown, with Ebola and Marburg already ruled out, raising concerns about a severe infectious or toxic agent,” the WHO said earlier this month, adding in its latest update that “further tests are to be carried out for meningitis.” Food, water, and environmental samples will also be analyzed, the health organization says, to check for any contamination with the as-yet unidentified pathogen.
WHO is supporting the local health authorities with their response with more than 80 community health workers trained to detect and report cases and deaths. “Further efforts are needed to reinforce testing, early case detection and reporting, for the current event but also for future incidents,” the organization says.
Disease outbreaks caused by pathogens in animals transferring to humans—a process known as zoonotic spillover—are becoming more common in Africa. Changing land use and climate change are two major drivers, as they can both increase contact between humans and pathogen-harboring wildlife. According to estimates from the WHO, outbreaks of diseases transmitted from animals to people increased by 63 percent in Africa between 2012 and 2022. The continent has seen multiple outbreaks of mpox in recent years, as well as clusters of Ebola and Marburg cases.
Late last year, another mysterious illness killed more than 70 people in the southwest of the DRC, many of them children. Symptoms in that outbreak were flu-like, and most patient samples tested came back positive for malaria. The outbreak was later attributed to respiratory infections aggravated by malaria.
This story originally appeared on WIRED Italia and has been translated from Italian.
Updated 2-27-2025 7:30 pm GMT: The piece was updated with statistics and information from the most recent WHO report on the outbreak.