Short communication: High frequency of β-lactam-resistant Staphylococcus aureus in artisanal coalho cheese made from goat milk produced in northeastern Brazil

Abstract

Reports of β-lactam-resistant Staphylococcus aureus in artisanal goat cheese are increasing, and this phenomenon is relevant to public health. The objective of the present study was to determine the prevalence of S. aureus strains carrying the blaZ and mecA resistance genes, as well as the genes encoding the staphylococcal enterotoxins SEA, SEB, SEC, SED, SEE, and TSST-1 in artisanal coalho cheese made from goat milk produced in northeastern Brazil. We used biochemical and molecular tests to characterize 54 S. aureus isolates found in artisanal coalho cheese collected from commercial establishments producing animal products in 11 municipalities of Pernambuco State, Brazil. A PCR analysis revealed that 42.6% (23/54) of the isolates were positive for the blaZ gene, and 7.4% (4/54) were resistant to methicillin by phenotypic testing. We did not detect mecA or any genes encoding enterotoxins. The presence of S. aureus carriers of the blaZ gene and the identification of methicillin-resistant S. aureus strains are of concern for the health of consumers of this type of cheese.

Characterisation of Staphylococcus aureus strains from milk and goat cheese and evaluation of their inhibition by gallic acid, nisin and velame of the Brazilian caatinga

“…For the milk samples, the mean counts in the 7 municipalities ranged from 1.18 × 10 1 to 1.29 × 10 3 CFU/mL, while for the cheese samples, the counts ranged from 8.32 × 10 4 to 6.46 × 10 5 CFU/g. Staphylococcus aureus is the pathogen most commonly isolated from milk, and goat derivatives, milkers and artisan cheesemakers are some of the potential transmitters of this microorganism along the milk chain (Castro et al ; Anderson et al ; Aragão et al ). Our study draws attention to a direct risk to the consumer given the probability of production of enterotoxins due to the quantitative populations of presumptive S. aureus in the cheeses from all the properties studied.…”

“…Goat milk and cheese are at risk of contamination by enterotoxigenic and multidrug‐resistant Staphylococcus aureus strains (Castro et al ). The pathogen is highly prevalent and is the most frequent contaminant in milk and goat milk products (Xing et al ; Castro et al ; Aragão et al ). Staphylococcus aureus remains on surfaces and utensils due to its ability to form biofilms.…”

Artisanal Brazilian Cheeses—History, Marketing, Technological and Microbiological Aspects

“…Staphylococci contaminations are probably the most frequent problem regarding artisanal cheeses [32,47,[73][74][75][76][77]. It is usually associated with the contaminations from the animals' skin or employees directly involved in the milking process, or even the manipulation during cheese-making.…”

A Label-Free Fluorescent Aptasensor for Detection of Staphylococcal Enterotoxin A Based on Aptamer-Functionalized Silver Nanoclusters

“…Moreover, the intake of SEA up to 50 ng (body weights of 70 kg) [11] can cause food poisoning and other diseases, as well as the exacerbation of various diseases [12,13]. For instance, it is also likely to cause life-threatening toxic shock [14,15]. Additionally, the cooking process may not eliminate the toxin in the contaminated food because of heat-resistant [13], proteolytically stable, and small monomeric proteins (molecular weight (MW) = 27 kDa) of SEA that can resist a series of harsh conditions [16].…”