Sixteen tribespeople, mainly children, have been afflicted over the past two months with symptoms of fever, paralysis and an extreme fear of water.
Victims tend to have convulsions and become rigid before death.
Rabies-infected vampire bats are a problem in several tropical areas of South America, especially in the Amazon region of Brazil and Peru.
The flying mammals usually swoop down and make small incisions with their teeth while victims are sleeping.
Those who suspect they have been bitten and exhibit small puncture wounds are being given a regimen of rabies shots.