Preclinical evaluation of a live attenuated bivalent Trichophyton vaccine for prophylaxis and post-infection treatment of dermatophytosis in rabbits

Background and Aim: Bovine trichophytosis is a contagious zoonotic dermatophytosis that adversely affects animal health and livestock productivity and poses an occupational risk to people in contact with infected cattle. Although live attenuated vaccines have contributed to disease control, evidence for bivalent formulations targeting multiple Trichophyton species remains limited. This study evaluated the prophylactic activity and post-infection outcomes of a live attenuated bivalent vaccine candidate containing Trichophyton verrucosum and a member of the Trichophyton mentagrophytes species complex in an experimental rabbit model. Materials and Methods: Thirty-three clinically healthy rabbits were allocated to a prophylactic group (Group I, n = 10), therapeutic group (Group IIa, n = 10), infected untreated histopathology subgroup (Group IIb, n = 3), and intact control group (Group III, n = 10). Group I received two intramuscular vaccinations 14 days apart and was challenged 21 days after the second vaccination, whereas Group IIa was experimentally infected before therapeutic vaccination. Clinical manifestations, body weight, rectal temperature, hematological parameters, mycological culture, and histopathological changes were evaluated. Clinical and histopathological assessments were descriptive and non-blinded.