Bacteria responsible for Hansen’s disease may have been lurking in rodents for centuries
Leprosy has been hiding out in red squirrels in Great Britain and Ireland, though the painful and disfiguring disease has rarely been transmitted between humans there since the Middle Ages.
The endangered bushy-tailed rodents (Sciurus vulgaris) have tested positive for leprosy-causing bacteria in several locations around the British Isles, researchers report November 11 in Science.
“It goes to show that once a disease has become extinct in humans, it could still exist in the environment if there was a suitable reservoir,” says study coauthor Stewart Cole, director of the Global Health Institute at the Swiss Federal Institute of Technology in Lausanne. In this case, squirrels seem to be ideal incubators for leprosy bacteria.