Free online medical education courses on cat scratch disease and Bartonella

Invisible International has released six new courses on Bartonella, the family of stealth bacteria best known for causing cat scratch disease and trench fever. Courses cover disease history, transmission, reservoir hosts, risk factors, disease manifestations, and diagnosis.

In the last few years, there has been a growing body of knowledge on the Bartonella family of bacteria, particularly Bartonella henselae, the causative agent of cat scratch disease. In this course series, a leading expert on Bartonellosis in mammals, Edward Breitschwerdt, DVM, provides a fascinating overview of the latest in clinical manifestations and diagnostic methodologies for detecting these evasive, slow-growing pathogens. His message to both physicians and veterinarians — Bartonella-related diseases are more common than previously known and these stealth organisms may be the culprit behind many illnesses of “unknown etiology.”

In humans, Bartonella henselae is typically transmitted by cat bites or scratches, sometimes by flea bites. Three to 10 days after inoculation, the infected may experience a fever and a lesion at the wound site. Swollen lymph nodes may appear one to two weeks later. Many report headaches, lack of appetite, weight loss, vomiting, and, occasionally, a sore throat. While most cases resolve without treatment, five to 20 percent of the infected exhibit severe symptoms of the disease. Complications can involve the eyes, nervous system, brain, heart, liver, spleen, skin, and musculoskeletal system. A major focus of this course series is to provide physicians veterinarians with new evidence to help them explore Bartonella as a differential diagnosis in their most confounding cases.

Breitschwerdt also presents some interesting evidence on possible Bartonella transmission by ants, spiders, mites, needle sticks, and ticks. Tick-to-human transmission is a controversial topic in infectious disease circles, but after reviewing the latest research (mostly from Europe), Breithschwerdt concludes that it is “highly likely.” He also reminds physicians to ask sick patients about their exposure to animals, since Bartonella often runs in families, infecting both pets and their human companions.

Edward Breitschwerdt, DVM, the course’s author, is a professor of medicine and infectious diseases at the North Carolina State University College of Veterinary Medicine. He is also an adjunct professor of medicine at Duke University Medical Center and a diplomate in the American College of Veterinary Internal Medicine (ACVIM). As a leading expert on bartonellosis, he directs the Intracellular Pathogens Research Laboratory in the Institute for Comparative Medicine and co-directs the Vector Borne Diseases Diagnostic Laboratory at NCSU. These courses are currently in review for CME credit by the American Academy of Family Physicians.

This project is funded by the Montecalvo Platform for Tick-Borne Illness Education, through Invisible International, a 501(c)(3) nonprofit foundation dedicated to reducing the suffering associated with invisible illnesses and social marginalization through innovation, education, and data-driven change projects. You can sign up to receive news and updates at:

Links to Bartonella courses: History of a hidden pandemic, Vectors and other modes of transmission, Reservoir hosts: Bats, cats, dogs, mice and men, Comparative infectious disease causation, Disease expression and host immunity, and Diagnosis of Bartonella species infections.

Image credit: ehaurylik @iStock