The Detection of Methicillin and Multiple Antibiotics Resistant Staphylococcus aureus in Dairy Products as Sold in Parts of Kaduna State, Nigeria

Dairy products sold through unregulated channels are potential sources of a variety of microorganisms that are involved in food poisoning. Staphylococcus aureus is a known example of bacteria causing food-borne diseases. Methicillin resistance is a prominent index in food hygiene studies. In this study, multiple antibiotics and methicillin-resistant Staphylococcus aureus in dairy products were studied. A total of 320 dairy product samples, comprising 80 each of fresh milk, nono (cultured skimmed, defatted milk), manshanu (milk fat), and kindrimo (full-fat or partially skimmed cultured milk), were examined for possible contamination by Staphylococcus aureus. The antibiogram and the presence of antibiotic-resistant phenotypes of MRSA were determined using the agar disk diffusion method. The Polymerase chain reaction (PCR) technique was employed to detect the mec A gene. A total of 28 (8.75%) of S. aureus was detected in the current study. There was a significant difference at p ≤ 0.05 in the proportion of S. aureus contamination among the dairy samples. Multiple antibiotic resistance index (MAR > 0.2) was 19 (67.86%). The cumulative occurrence of MRSA for this study was 20 (71.43%), with 3.75%, 3.75%, 10.0%, and 7.5% occurrence in Nono, Kindrimo, Manshanu, and Fresh milk, respectively. The highest resistance to Ceforxitin was seen in Manshanu (77.8%), while the lowest was seen in Nono (50%). There was no significant difference at p≤0.05 in the proportion of Ceforxitin positive samples among the four dairy products. A total of 11 (39.29%) of the isolates haboured the Mec A gene. Antibiotic–resistant bacteria are at risk of being transferred to humans via milk. For safe and healthy milk consumption, new hygiene policies and management practices should be considered to increase food safety.