Dr. Edward Breischwardt explained that dogs and humans have similar disease states with Bartonella.
Dogs infected with Bartonella develop antibodies, and cutoff levels for a “positive” vary widely. But over approximately months, the antibodies drop into the negative range.
This may be another reason Bartonella is so common yet tests negative via antibody testing.
It really is just more example of why Bartonella is an exceptional stealth infection.
References
Lesson 1: Diagnosis of Bartonella Species Infections | VectorWise CME (opens in new tab). Accessed August 8, 2026.