title: Methicillin-resistant Staphylococcus aureus (MRSA) in slaughtered pigs and abattoir workers in Italy.
abstract: Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogen present in the hospital environment (HA-MRSA), in the community (CA-MRSA) and in livestock, including pigs (LA-MRSA). MRSA may enter the human food chain during slaughtering and may infect humans coming into direct contact with pigs or pork products. This study aimed to determine the prevalence and characteristics of MRSA isolated from pigs and workers at industrial abattoirs in southern Italy. A total of 215 pig nasal swabs were screened for the presence of MRSA using PCR. An MRSA isolate was detected from each mecA/nuc PCR-positive sample and characterized by spa-typing, Multi-Locus Sequence Typing, SCC-mec and Panton-Valentine Leukocidin (PVL), and also tested for the production of staphylococcal enterotoxins (SEs). Eighty-one MRSA isolates (37.6%) were obtained from the 215 pig nasal swabs; 37 of these isolates were further characterized, and showed 18 different spa-types and 8 different STs. The most frequently recovered STs were ST398 (CC398-t034, t011, t899, t1939 - 43.2%) followed by ST8 (CC8-t008, t064, t2953, t5270 - 24.3%) and ST1 (CC1-t127, t174, t2207 - 10.8%). Nine MRSA isolates were obtained from the 113 human swabs; the isolates showed 5 different spa-types and 5 different STs, including the novel ST2794 (t159). The most representative STs recovered were ST1 (CC1-t127) and ST398 (CC398-t034) (33.3%). None of the MRSA isolates showed the ability to produce SEs and PVL and all resulted resistant to two or more classes of antimicrobials. This study shows the great genetic diversity of MRSA strains in slaughtered pigs and in abattoir employees in Italy, and clearly demonstrates the need for improved hygiene standards to reduce the risk of occupational and food-borne infection linked to the handling/consumption of raw pork containing MRSA.
authors.affiliation: Department of Science of Agriculture, Food and the Environment (SAFE), University of Foggia, Foggia, Italy. Electronic address: giovanni.normanno@unifg.it.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Normanno
authors.affiliation: Department of Emergency and Organ Transplants, University of Bari, Bari, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Dambrosio
authors.affiliation: Department of Soil Sciences, of Plants and Food, University of Bari, Bari, Italy.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Lorusso
authors.affiliation: Veterinary Quality Manager in Food Sector, Bari, Italy.
authors.forename: Georgios
authors.initials: G
authors.lastname: Samoilis
authors.affiliation: Department of Science of Agriculture, Food and the Environment (SAFE), University of Foggia, Foggia, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Di Taranto
authors.affiliation: Experimental Zooprophylactic Institute of Apulia and Basilicata, Foggia, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Parisi
mesh_terms: D000003:Abattoirs; D000328:Adult; D000818:Animals; D001427:Bacterial Toxins / Q000235:genetics; D004768:Enterotoxins / Q000096:biosynthesis; D005098:Exotoxins / Q000235:genetics; D059022:Food Safety; D006801:Humans; D007558:Italy; D007956:Leukocidins / Q000235:genetics; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D009666:Nose / Q000382:microbiology; D016273:Occupational Exposure; D000069466:Red Meat / Q000382:microbiology*; D034421:Sus scrofa; D013552:Swine / Q000382:microbiology*
chemical_list: D001427:Bacterial Toxins; D004768:Enterotoxins; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin
keywords: Abattoir workers; Food safety and occupational risk; MRSA; Pigs