Species of Borreliafrom a Colombian Bat (Natalus tumidirostris)

ALTHOUGH recurrent and relapsing fevers occur in Colombia, the aetiological agents are seldom diagnosed. From Colombia only two of the six recognized forms of arthropod-borne relapsing fevers have been reported: epidemic cosmopolitan relapsing fever caused by Borrelia recurrentis(synonyms B. obermeiri, B. novyi) and transmitted by lice (Pediculus humanus), and the endemic central and South American form of relapsing fever caused by B. venezuelensis(synonym B. neotropicalis) transmitted in nature to man, monkeys and marsupials by the soft ticks (Ornithodorosrudis, O. talaje, O. turcicate, O. rostrata and O. megnini). During the past 10 yr no arthropod-borne relapsing fevers have been reported from Colombia but there have been several suspicious cases in the department of Santander, where O. rudisis not uncommon8.