A novel virus has been identified as the possible cause of a common but mysterious disease that kills a significant number of pet snakes all over the world, thanks to research led by scientists at the University of California, San Francisco (UCSF) -- and three snakes named Juliet, Balthazar and Larry. The virus,
previously1 not thought to infect snakes at all, appears to cause "
inclusion(包含) body disease." Long the
bane(毒药,祸害) of zoo officials and exotic pet owners, the deadly illness spreads among
boas(蟒蛇) and pythons in
captivity2, causing micro
clumps3 of clustered proteins to form inside the snake, leading to
bacterial4 infections, neurological problems,
anorexia5(厌食) and
withering6, leading to death.
The new work, described this week in the American Society for Microbiology's new open-access journal mBio, paves the way toward developing diagnostics and treatments, which may make it possible to
eradicate7 the disease from snake collections worldwide.
"It's a
devastating8 disease when it gets into a collection, zoo or
aquarium9 because it's
essentially10 fatal every time," said Joe DeRisi, PhD, the senior author of the study, a Howard Hughes Medical Institute
investigator11 (HHMI) and
vice12 chair of the Department of Biochemistry and Biophysics at UCSF.
Surprisingly, he said, the cause of the illness appears to be a completely new set of viruses of a type known as an
arenavirus(沙粒病毒). The discovery came as a complete a shock to the team of scientists because, while arenaviruses are common in
rodents13 and cause extremely nasty infections in other mammals, nobody knew they could infect
reptiles14.
"Now we have found that they infect snakes, as well," said Mark Stenglein, PhD, a postdoctoral fellow at UCSF who is the first author on the paper.
Stenglein, DeRisi and their colleagues
isolated15 at least two strains of the arenaviruses from half a dozen snakes
afflicted16 with inclusion body disease. They could find no traces of the same viruses in snakes that were free from disease.
Arenaviruses infect mostly rodents but occasionally people, and can cause fatal hemorrhagic diseases like Lassa fever, which kills thousands of people every year in Africa. There is no evidence, however, that a snake has ever transmitted an arenavirus infection to a person despite the fact that snake owners and veterinarians(兽医) handle infected snakes all the time, said DeRisi.