Since 2005, more than 50 animals at Sierra Leone’s Tacugama Chimpanzee Sanctuary have died from a condition called epizootic neurologic and gastroenteric syndrome (ENGS). Baffled by this inexplicable disease, the sanctuary’s veterinarians collaborated with an international team of experts led by Tony Goldberg of the University of Wisconsin at Madison.
Their search for pathogens in the tissues of the deceased primates revealed a likely suspect—a new species of bacteria from the genus Sarcina. Goldberg notes that a handful of previous studies had tentatively linked Sarcina bacteria to serious gastrointestinal disease in humans and animals, but without clearly demonstrating that these microbes were the cause.
Through in-depth analysis of this novel species, the researchers found intriguing clues that could explain its pathogenic effects. “It has a particular biochemical mechanism that, under the right conditions, produces a lot of carbon dioxide and ethanol,” says Goldberg. These chemicals could respectively produce the gastrointestinal bloating and neurological symptoms associated with ENGS. The researchers also identified strategies to fight infection, including specific antibiotics and dietary changes that can ‘starve’ the bacteria in infected animals.
Work at the sanctuary has already helped one chimpanzee to recover, reports Goldberg, although they are waiting on final confirmation of the ENGS diagnosis. “If so, that’s big news, because that means we’ve learned something and applied it successfully,” he says.
The implications of this work could reach far beyond Tacugama. Goldberg says his team has been contacted not just by other veterinarians, but also clinicians intrigued by the potential threat that certain Sarcina species may pose to human health.