Resistência antimicrobiana de Staphylococcus aureus isolados de produtos de origem animal

Abstract

Staphylococcus aureus is a commensal microorganism of the skin and mucous membranes of animals and humans and is considered an opportunistic agent responsible for food poisoning. Another threat to public health relates to its antimicrobial resistance capacity, which has been detected in isolated strains of various animal products and is associated with the indiscriminate use of antimicrobial agents in animal production, which warns of the transmission of this microorganism through food. The objective of this study was to investigate the occurrence of antimicrobial resistant Staphylococcus aureus in handmade coalho cheese, beef ground and pork and chicken meat. From each animal product, 3 market samples were acquired in Pernambuco, Brazil, which were submitted to microbiological analysis for coagulase positive Staphylococcus and S. aureus counts. S. aureus strains were isolated, submitted to the antimicrobial susceptibility test to nine antimicrobials used in the human and veterinary clinics, and the antimicrobial multiresistance was then evaluated and the Multiple Antimicrobial Resistance (MAR) index was calculated. Contamination in all types of products was verified by S. coagulase positive, with an equal count for S. aureus, ranging from 2.4 x 103 CFU/g in the pork meat to 2.2 x 106 CFU/g in chicken meat. Among the isolated strains, 37.5% (45/120) were confirmed as S. aureus, with the highest occurrence in pork with 63% (19/45) and handmade coalho cheese with 37% (14/45), followed by ground beef with 33% (10/45) and chicken meat with 6.7% (2/45). Regarding antimicrobial resistance, pork meat, followed by handmade coalho cheese and chicken meat had the highest number of resistant strains. There was a higher resistance to tetracycline, with 33.3% (15/45) of S. aureus strains, followed by penicillin G with 24.4% (11/45), erythromycin with 8.8% (4/45), clindamycin with 6.6% (3/45) and cefoxitin with 2.2% (1/45), with 4 (8.8%) strains considered multidrug-resistant (MDR), 3 (6.6%) MLSc (constitutive resistance to macrolide, lincosamide and streptogramin), 1 (2.2%) MRSA (methicillin-resistant S. aureus) and 17 (37.7%) from potential sources of high-risk contamination, with MAR index ≥ 0.2. There was no resistance to gentamicin, ciprofloxacin, chloramphenicol and sulfazotrim. It is concluded that the products of animal origin analyzed showed contamination by S. aureus and may be reservoirs of strains resistant to antimicrobials, representing a potential risk to the health of the population.