People keep trespassing near cave filled with bats infected by Ebola’s cousin
You don’t want to get Marburg virus disease (MVD). Formerly known as Marburg hemorrhagic fever, it is in the same family as Ebola and has many of the same deadly symptoms, including massive internal bleeding and organ failure.
Fortunately, epidemiologists have long worked to identify and monitor locations designated as known reservoirs of Marburg virus. These include places like Python Cave, inside Uganda’s Queen Elizabeth National Park. But according to a surprising report published in the journal Current biology Visitors to the scenic ecological reserve this week systematically ignored clear warnings to stay away from the caverns. After nearly 9,000 hours of recorded activity, the authors documented more than 200 human incursions into Python Cave, including international tourists and schoolchildren. Although no reported cases are linked to these cases, the study authors warn that future contact could put visitors (and countless others) at risk of contracting the nightmare virus.
Cases of Marburg virus disease are fortunately rare, but they remain a very real threat. Transmission from animals to humans most likely occurs through the Egyptian fruit bat (Rousettus aegyptiacus), which lives in the tropical climates of Africa, the Middle East and the Indian subcontinent. Symptoms begin with chills, fever, headache, and muscle pain before quickly worsening. About five days after initial onset, patients can expect a rash, nausea and vomiting, as well as diarrhea. This quickly progresses to massive internal bleeding and multiorgan failure.
An outbreak of Marburg disease easily reaches a mortality rate of almost 90 percent, and there simply aren’t many effective treatments yet. Even with symptomatic care, only half of all patients survive their ordeal. As if all this wasn’t scary enough, the World Health Organization warns that the Marburg virus could spread to pandemic proportions under the right circumstances.
Places like Python Cave are particularly important to researchers because of their viral reservoir capabilities. Egyptian fruit bats carrying the Marburg virus are confirmed to roost in the cave, and Queen Elizabeth National Park prohibits visitors from approaching the designated viewing platform located approximately 100 feet from the cave entrance.
For this study, researchers initially installed six solar cameras around the site to document animal interactions at Python Cave, particularly the bat-hunting habits of African leopards (Panthera pardus pardus) and spotted hyenas (Crocuta crocuta). Between February and June 2025, the study authors confirmed that more than 14 different animal species interacted inside the cave on 321 occasions, including leopards and monkeys catching bats.
However, they were also shocked to identify the presence of a 15th species: Homo sapiens. In at least 214 separate cases, people broke park rules to get closer to Python Cave. In only one case did anyone wear a mask.
The researchers explicitly cautioned that their observations do not constitute “virological evidence of transmission.” Instead, they hoped their data would offer a direct and rare insight into the complex interactions between humans, animals and diseases in an ecological context.
“Our results reflect risk at the landscape level: not only the presence of reservoir hosts, but also the behaviors, interactions, and human access patterns that shape exposure,” the authors wrote.
But even if visitors in 2025 haven’t contracted Marburg virus disease, the next person may not be so lucky. The last confirmed cases at Python Cave in 2007 and 2008 involved two tourists, and only one survived.
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