The tropism of foot-and-mouth disease virus in African buffalo (Syncerus caffer) using BaseScope™ in situ hybridisation

BaseScope™ in situ hybridisation (Advanced Cell Diagnostics, USA) was used to detect foot-and-mouth disease virus (FMDV), species Aphthovirus vesiculae , in formalin-fixed paraffin-embedded tissues of African Buffalo ( Syncerus caffer ) (n = 15). The buffalo originated from the Kruger National Park and were culled as part of the park’s population management strategy. Foot-and-mouth disease viral RNA was detected consistently in the tonsil and lungs, less frequently in the retropharyngeal lymph nodes and interdigital skin and very rarely in the pharyngeal tissue. Other tissues (tip of the ear, eyelid, tongue, lip and coronary band) were evaluated with BaseScope™ and none of these tissues were optimal to detect FMDV-positive animals and carriers. The successful application of this novel diagnostic modality revealed that the tropism of FMDV in carrier African buffalo is the tonsils and lungs.