Bartonella henselae is a type of bacteria that can cause infections in humans. It is primarily transmitted through bites or scratches from infected cats, particularly kittens. This bacterium is known for causing cat scratch fever, which can lead to symptoms like fever, swollen lymph nodes, and fatigue. In addition to cat scratch fever, Bartonella henselae has been linked to other health issues, especially in individuals with weakened immune systems. Diagnosis typically involves blood tests, and treatment usually includes antibiotics. Preventive measures include proper hygiene and avoiding rough play with cats.