bartonella washoensis bartonella washoensis bartonella washoensis is a bacterium from the genus bartonella which was first isolated from a dog with mitral valve endocarditis. bartonella washoensis can infect squirrels but also can cause meningitis in humans. bartonella washoensis scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: hyphomicrobiales family: bartonellaceae genus: bartonella species: b. washoensi binomial name bartonella washoensibreitschwerdt and kordick 2000