The Disease Du Jour 180: Pigeon Fever with Dr. Erika Machtinger

In this episode of Disease Du Jour, host Carly Sisson speaks with Dr. Erika Machtinger, an Associate Professor of Entomology and Vector-Borne Disease Team Lead at Pennsylvania State University, about pigeon fever in horses. The discussion covers the bacterium *Corynebacterium pseudotuberculosis* as the cause of pigeon fever, its transmission via flies and environmental contamination, and its shifting epidemiology across the U.S., now increasingly seen in the Midwest and East Coast due to climate change, horse movement, and improved diagnostics. Dr. Machtinger emphasizes that while the disease is not reportable, effective biosecurity requires a holistic approach—focusing not just on the horse but on the entire environment, especially fly control and waste management. She highlights the three clinical forms: external abscesses (the classic 'pigeon chest' presentation), internal abscessation, and ulcerative lymphangitis, with prognosis varying significantly by form. Early detection and integrated management involving both veterinarians and entomologists are key to reducing risk and preventing outbreaks. The episode underscores that pigeon fever is not a seasonal disease in all regions—its activity correlates with fly presence, which is extending due to longer warm seasons. Dr. Machtinger stresses that treating the environment is as critical as treating the horse, recommending manure removal, fly traps, fans, and barriers. She also encourages horse owners to consult their state’s extension office for expert guidance. The episode concludes with a strong call to action: think beyond the individual horse and manage the entire facility ecosystem to break the transmission cycle.