4. Pathology of African swine fever
Pedro J. Sánchez‐Cordón, Beatriz Vidaña, Aleksija Neimanis, Alejandro Núñez, Erika Wikström, Dolores Gavier‐Widén
Abstract
African swine fever (ASF) is a haemorrhagic viral disease of domestic pigs and wild boar (both Sus scrofa species) that seriously impacts pig production worldwide. Pathology plays a key role not only in identifying and characterising macroscopic and histopathological lesions, but also in studying pathogenesis, thus complementing other disciplines to provide a broad understanding of host-virus interactions, which contributes to the development of vaccines and therapies. The aim of the present chapter is to provide a compilation of the most characteristic macroscopic and histopathological lesions associated with the different clinical forms of ASF (peracute, acute, subacute and chronic). Another aim is to present the current state of knowledge regarding ASF pathogenesis, with special attention to target cells, virus distribution and virus load in multiple organ locations and its correlation with the appearance of clinical signs and lesions from early stages to terminal disease. For that purpose, the chapter includes a complete collection of original macroscopic and microscopic photographs, the latter including illustrations of haematoxylin and eosin-stained sections and immunohistochemistry to identify the ASF-virus (ASFV). The photographs were obtained from experimental infections with ASFV isolates of different virulence carried out over the last two decades in different research centres. The purpose is to provide a reference that may be useful for the early recognition of ASF by veterinary practitioners working in the field and researchers focused on characterising new ASFV isolates or testing new vaccines and treatments.