Is bartonellosis a contagious desease?

One type is: There are several different bartonella species, each causing a different disease, in animals and humans. If you are talking peron to person transmission, the only apparent form that may spread this way is Oroya fever. See this page: https://rarediseases.org/rare-diseases/bartonellosis/
Yes. Bartonellosis can be caused by a family of bartonella organisms. The most common one being cat-scratch disease.