People keep trespassing near bat-filled cave filled with Ebola’s cousin

You do not want to contract Marburg virus disease (MVD). Formerly known as Marburg hemorrhagic fever, it belongs to the same family as Ebola and displays many of the same fatal symptoms including massive internal bleeding and organ failure. 

Luckily, epidemiologists have long worked to identify and monitor locations designated as known Marburg virus reservoirs.These include places like Python Cave inside Uganda’s Queen Elizabeth National Park. But according to a startling report published in the journal Current Biology this week, visitors to the scenic ecological reserve have routinely ignored clear warnings to stay far away from the caverns. After almost 9,000 hours of recorded activity, authors tallied over 200 human incursions into Python Cave, including international tourists and school children. While no reported cases were tied to these instances, the study’s authors warn that future contact could put visitors (and untold others) at risk of contracting the nightmarish virus.

Cases of Marburg virus disease are thankfully 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 tropical climates across Africa, the Middle East, and the Indian subcontinent. Symptoms begin with chills, fever, headache, and muscle pain before quickly becoming more severe. Around five days after the initial onset, patients can expect a skin rash, nausea and vomiting, as well as diarrhea. This soon progresses to massive internal hemorrhaging and multi-organ failure.

An outbreak of Marburg disease easily reaches a nearly 90 percent mortality rate, and there still simply isn’t much in the way of effective treatments. Even with symptomatic care, only half of all patients survive their ordeal. If all that wasn’t scary enough, the World Health Organization warns the Marburg virus could spread to pandemic proportions under the right circumstances.

Places like Python Cave are particularly important for researchers due to their capacities as viral reservoirs. Egyptian fruit bats carrying Marburg virus are confirmed to roost in the cave, and Queen Elizabeth National Park prohibits visitors from getting any closer than the designated observation platform positioned about 100 feet from the cavern entrance. 

For this study, researchers initially installed six solar-powered 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’s authors confirmed over 14 different animal species interacting inside the cave on 321 occasions including both leopards and monkeys catching bats.

However, they were also shocked to identify the presence of a 15th species: Homo sapiens. During at least 214 separate instances, people violated park rules to move closer to Python Cave. In only one instance did someone wear a mask.

Researchers explicitly cautioned that their observations are not “virological evidence of transmission.” Instead, they hoped their data offers a rare, direct look at the complex interactions between humans, animals, and diseases in an ecological setting.

“Our findings reflect landscape-level risk: not only the presence of reservoir hosts, but the behaviors, interactions, and human-access patterns shaping exposure,” wrote the authors.

But even if the people visiting in 2025 didn’t contract Marburg virus disease, the next person may not be so lucky. Python Cave’s last confirmed cases in 2007 and 2008 involved two tourists—and only one survived.

 

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