C35 | Salmonella spp. in carcasses and rectal swabs of wild boars from the 2024-2025 hunting season in Apulia and Basilicata

F. Petruzzi^1|2, L. Del Sambro², A. Bianco², L. Capozzi², A. Iannacci³, P. Raimondi⁴, D. Belluscio², G. Normanno¹, A. Parisi², P. Di Taranto². | ¹Dip. di Scienze Agrarie, Alimenti, Risorse Naturali e Ingegneria, Università degli Studi di Foggia; ²Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata; ³Servizio Igiene degli alimenti di origine animale A.S.L. Foggia; ⁴Dip. di Prevenzione della Sanità e Benessere Animale-Area B, Potenza.

Purpose. During the 2024-2025 hunting season, sampling was carried out to obtain a preliminary estimate of the circulation of Salmonella spp. in wild boars hunted in Puglia and Basilicata, with the aim of collecting useful data to better define the infectious risk associated with the handling and consumption of the meat derived from them. Methods. The survey was conducted on 148 wild boar specimens shot during the 2024-2025 hunting season. Specifically, 106 samples were collected from carcasses and 42 rectal swabs were collected using a non-destructive method (sponges). Carcass sampling was carried out at a Game Processing Centre (CLS), while rectal swabs were taken in the field. The isolation of Salmonella spp. was carried out following the protocol set out in ISO 6579-1:2017. An isolate attributable to Salmonella spp. per positive sample was confirmed by MALDI-TOF MS (Matrix-Assisted Laser Desorption/Ionisation Time-of-Flight Mass Spectrometry). Each strain identified as Salmonella spp. was subjected to serotyping according to ISO/TR 6579-3:2014 and to minimum inhibitory concentration (MIC) determination using commercial Sensititre™ EUVSEC 3 plates (Thermo Scientific). The MIC results were interpreted using the reference breakpoints reported in EUCAST 2025 version 15. Results. Overall, Salmonella spp. was detected in 5/148 samples (3.37%). Specifically, in 3 out of 78 carcasses (3.84%) from Basilicata (PZ), it was possible to isolate 2 strains of S. Kasenyi (38:e,h:1.5) and 1 strain of S. Kottbus (6.8:e,h:1.5). Two rectal swabs out of 42 (4.76%) tested positive for S. ser. II (41:z:1.5) (Puglia - FG) and for S. Kasenyi (Basilicata - PZ). All isolates were sensitive to the antimicrobials tested. Conclusions. The results of this preliminary investigation highlighted the presence of Salmonella spp. in 3.37% of the samples examined, confirming that wild boar is a species capable of spreading this microorganism in the environment and, potentially, transferring it to consumers. With regard to the identification of isolates, the detection of S. Kasenyi and S. Kottbus in carcasses is of interest. While there are no reports of human cases for S. Kasenyi, already isolated from wild boars from Campania, there are several reports of outbreaks caused by S. Kottbus in the United States, the Canary Islands and Germany. In addition, Denmark has reported a case of S. Kottbus carrying the blaNDM-1 gene, which confers resistance to carbapenems. In light of the current evidence, there are no data available on the presence of Salmonella ser. II (41:z:1,5) in wild boars hunted in Italy, nor are there any reports on this in European scientific literature. Finally, with regard to antimicrobial resistance potential, in our investigation all isolates showed a high sensitivity profile to the molecules tested. In conclusion, the identification of S. Kasenyi and S. Kottbus in wild boar is of interest for the ecological surveillance of salmonellosis and highlights the potential role of this species as a reservoir of minor serotypes, with epidemiological implications yet to be clarified.