ALESSIO MANFREDI1*, PATRIZIO LORUSSO1, ANNAMARIA PANDISCIA1, GIUSEPPINA MARILIA TANTILLO2,
GIANCARLO BOZZO1, VALENTINA TERIO1
|
1 Department of Veterinary Medicine, University of Bari, Provincial Road to Casamassima Km 3, 70010 Valenzano, Italy. * Corresponding author; E-mail: a.manfredi21@studenti.uniba.it Abstract Vibrio spp. are gram-negative bacteria responsible for foodborne illness associated with consumption of raw or undercooked shellfish. In particular, Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholerae are common human-pathogenic vibrios that are associated with clinical syndromes that can range from mild gastroenteritis to life-threatening primary septicemia.Therefore, the aim of the study is the evaluation of the presence of V. parahaemolyticus, V. vulnificus and V. cholerae in shellfish marketed in south Italy.During the period between December 2022 and January 2023, 36 samples of purified live bivalve molluscs were collected. Then, the culture method described in International Standard ISO 21872-1:2017 was applied for the detection of V. parahaemolyticus, V. vulnificus and V. cholerae. The characteristic colonies, isolated on TCBS and CHROMagar™ Vibrio, were confirmed by PCR through the detection of toxR gene for V. parahaemolyticus (Vp-toxR), prVC region for V. cholerae and VVH region for V. vulnificus. 5/36 samples tested positive for Vibrio parahaemolyticus with a 13,9% positivity rate, while no samples tested positive for Vibrio cholerae and Vibrio vulnificus. Although some samples were positive for Vibrio parahaemolyticus, the pathogenicity of the strains cannot be established because of the absence of analysis of virulence genes such as “tdh” and “trh”; thus, additional analyses are needed. However, the presence of Vibrio spp. during times of the year when temperatures should be lower and unsuitable for the growth of these microorganisms emphasizes both how climate change influences the presence of these microorganisms in seafood and how the current purification methods are ineffective in eradicating shellfish from these pathogens. In addition, Commission Regulation (CE) 2073/2005, which lays down the microbiological criteria for shellfish placed on the market, don’t provide any kind of criteria for the presence of these pathogens.Thus, the presence of Vibrio spp. in winter season, the ineffectiveness of current purification methods and the lack of microbiological limits suggest how the detection of Vibrio spp. in shellfish samples is very important to prevent emerging health risks. Keywords: shellfish; Vibrio spp.; food safety. |