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Medical Dictionary

Rickettsiales

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noun plural Rick·ett·si·a·les \ri-ˌket-sē-ˈā-(ˌ)lēz\

Medical Definition of Rickettsiales

  1. :  an order of small pleomorphic gram-negative bacteria that are obligate parasites living in vertebrates or in arthropods which often serve as vectors of those parasitic in vertebrates and are placed in the families Anaplasmataceae, Bartonellaceae, and rickettsiaceae




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