Scientists set up cameras in Uganda’s Marburg virus reservoir, capturing rare footage of wildlife and humans interacting in the site and raising concerns about spillover risk.
Scientists monitoring Uganda’s Python Cave captured animals and humans visiting a bat-filled cave that is a known Marburg virus hotspot, offering a rare window into zoonotic transmission risk.
ADVERTISEMENT
ADVERTISEMENT
Python Cave in Uganda is a known natural reservoir for Marburg virus, a deadly haemorrhagic fever virus, transmitted to people from fruit bats.
Over 8,832 hours of footage was recorded between 16 February and 23 June 2025, which was published in Current Biology. The researchers observed multiple incursions in the cave and its surroundings – totalling 321 detections of at least 14 different species.
These included vultures, baboons, blue monkeys, eagles, leopards, and humans.
Zoonotic virus spillover from animals to humans is not rare, however, witnessing these dynamics first-hand is uncommon.
“This represents a significant opportunity for human exposure at this known Marburg-virus bat reservoir,” the authors wrote in the report.
The researchers noted that these observations are not virological evidence of transmission but as a “rare ecological lens” into a real-world spillover setting – structured, repeated, multi-trophic, and unfolding at a known viral hotspot.
They said that models of spillover suggest multiple ways by which viruses jump hosts, including direct contact with the reservoir, indirect contact via intermediate hosts, and through environmental pathways such as contaminated fluids or surfaces.
Careless human action
Despite the Uganda Wildlife Authority creating an observation station at a safe distance from the cave to prevent human spillover events, the cameras captured 214 people, from school, research and tourist groups.
Only one of them was wearing a mask and many approached the cave mouth, which violates the national park rules requiring visitors to remain at least 30 metres away.
“This is particularly concerning during bat birthing pulses, when viral shedding risk is elevated,” the authors noted.
They added that the new report observations challenge the assumption that spillover interfaces are hidden, rare, or inaccessible.
Marburg outbreaks in the past
Marburg virus was first detected in 1967 after two simultaneous outbreaks in Marburg and Frankfurt in Germany, and in Belgrade, Serbia. These outbreaks were associated with laboratory work using African green monkeys imported from Uganda.
Since then, outbreaks and sporadic cases have been reported in Angola, the Democratic Republic of the Congo, Equatorial Guinea, Ghana, Guinea, Kenya, South Africa, Tanzania, and Uganda.
The Python cave was linked to the death of a Dutch woman in 2008 who contracted the virus after visiting the cave in Uganda.
The virus often starts with high fever, severe headache, and muscle aches and pains. Symptoms also include diarrhoea, abdominal pain and cramping, nausea, and vomiting.
In fatal cases, death occurs most often between eight and nine days after symptom onset, usually preceded by severe blood loss and shock. There are currently no approved vaccines or treatments.
