The Lawsonia Paradox: The Hidden Burden of Silent Disease.

Lawsonia intracellularis, the etiologic agent of porcine proliferative enteropathy (PPE), represents a growing challenge for modern swine production systems. The infection often occurs in a subclinical form and, together with limited awareness of its true production impact, may delay diagnosis and the timely adoption of control measures. In our opinion, this under-recognition of subclinical infection represents the greatest barrier to successful PPE control. Disease management is further complicated by frequent co-infections, limitations of currently available diagnostic tools, and the progressive reduction in routine antimicrobial use, which has revealed the true burden of PPE under commercial conditions. We therefore argue that vaccination should no longer be considered a stand-alone preventive measure, but rather the cornerstone of an integrated, farm-specific management strategy combining accurate diagnostic interpretation, optimized production flows, biosecurity, nutritional management, and continuous veterinary-farmer collaboration. Drawing on both published evidence and the long-term field experience of the authors, this Opinion discusses the key challenges limiting effective PPE control and proposes a practical framework to improve disease recognition, prevention, and sustainable management under commercial production conditions.