Objective: To assess the frequency of class 1 integrons among isolates of Salmonella enterica producing different types of beta-lactamases from the health region of Tortosa, and to attempt to establish the resistance genes located within their variable regions.
Methods: The presence of class 1 integrons and of aadA1, aadA2, dfrA1, tem-1, oxa-1 and pse-1 resistance genes within their variable regions was investigated by PCR in 100 ampicillin-resistant isolates of S. enterica (30 S.