The Hu-Flu
Virus from ecotourists likely killed endangered wild gorillas
In late June 2009, researchers in Rwanda noticed a female mountain gorilla coughing as she fed in her forest home. Within days, she was dead – and a new study concludes that she and an infant gorilla were killed by a virus that appears to have spread from human visitors. The news highlights the risk that species-jumping pathogens can pose to people and endangered species alike.
“We usually think of viruses as jumping from wildlife to humans, but what we often don’t realize is that this is a two-way highway,” says Gustavo Palacios, the study’s lead author and a researcher at Columbia University’s Center for Infection and Immunity (CII) in New York City.
The threats that pathogens like the avian and swine flu viruses pose to humans are well publicized. Less discussed are the diseases that humans can pass on to our closely-related ape relatives. That threat is particularly relevant in Rwanda, Uganda and the Democratic Republic of Congo, where the world’s 786 remaining mountain gorillas (Gorilla beringei beringei) live in 2 national parks popular with tourists.
“An ecotourism industry for viewing human-habituated mountain gorillas in the wild is thriving in all 3 countries,” Palacios’ team notes in Emerging Infectious Diseases. The visitors help “ensure the sustainability of the species by generating much-needed revenue and increasing global awareness,” they add. “Tourism, however, also poses a risk for disease.”
Particularly problematic are respiratory diseases, which account for 20% of sudden deaths among gorillas (behind poaching-related trauma). To protect the gorillas, all three governments restrict tourist numbers and proximity, and the Congo mandates that visitors wear masks. But “the frequency and severity of respiratory disease outbreaks among mountain gorillas… have recently increased,” the researchers report. From May through August 2008, for instance, outbreaks occurred in 4 gorilla groups in Rwanda.
Researchers recorded a fifth outbreak on June 28, 2009 with the discovery of the coughing female in a group known as “Hirwa.” Ultimately, researchers documented moderate to severe respiratory disease in 11 of the group’s 12 members. They gave drugs to 5 of the animals to help fend off the sickness.
Now, tissue samples taken from the two dead gorillas have revealed the probable cause: A human metapneumovirus (HMPV). The virus is already known to have killed wild chimpanzees exposed to human tourists, so it is not surprising it would kill gorillas too, the researchers suggest. Where, exactly, the virus came from is a mystery, although tests show it is closely related to strains circulating in South Africa, over 1,000 miles away.
The findings, says CII director W. Ian Lipkin, suggest that “conservation efforts must be expanded to protect wild animals from human pathogens to which they likely lack immunity.” – David Malakoff | March 31, 2011
Source: Gustavo Palacios et al. (2011). Human Metapneumovirus Infection in Wild Mountain Gorillas, Rwanda Emerging Infectious Diseases
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The tourists and park management are directly responsible for these deaths. The 7 meter proximity rule is a complete joke and is simply not enforced to any degree. A lot of tourists even make direct contact with the gorillas without being warned by park guides. How they get away with this beggars belief, it really does.
At least the Congo make tourists wear masks, but why is this not enforced at Bwindi and Volcanoes? Surely this would cause a relatively substantial reduction to the risk of airbourne diseases?
The priority should be with the gorillas health, not the tourists. The lengths we have to go to in order to save animals from ourselves is nothing short of disgraceful.