Livestock-associated methicillin-resistant Staphylococcus aureus responsible for human colonization and infection in an area of Italy with high density of pig farming

Abstract

BackgroundLivestock-Associated MRSA (LA-MRSA) belonging to ST398 lineage, common among pigs and other animals, emerged in Central and Northern Europe, becoming a new risk factor for MRSA among farm workers. Strains belonging to ST398 can be responsible for human colonization and infection, mainly in areas with high livestock-farming. The aim of this study was to investigate the occurrence of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) human colonization and infections in an area of the Lombardy Region (Italy), the Italian region with the highest density of pig farming.MethodsIn the period March-April 2010, 879 nasal swabs were taken from subjects at admission to a local hospital serving an area of the Lombardy Region devoted to agriculture and farming. In the period March 2010-February 2011, all MRSA strains from community-acquired infection (CAI) observed in the same hospital, were collected. Molecular characterization of the isolates included SCCmec typing, spa typing and multilocus sequence typing (MLST).ResultsOut of 879 nasal swabs examined, 9 (1%) yielded MRSA. Five strains were assigned to sequence type (ST)398 (spa t899, 3 isolates; t108 and t2922, 1 isolate each) and were therefore categorized as LA-MRSA. The other 4 isolates were likely of hospital origin. No strains were positive for Panton-Valentine Leukocidin genes. Twenty MRSA isolates were detected from CAI, 17 were from skin and soft-tissue infections and 3 from other infections. An MRSA isolate from otitis externa was t899/ST398 and PVL-negative, hence categorized as LA-MRSA. Four isolates were assigned to t127/ST1. Eight strains were PVL-positive community acquired (CA)-MRSA and belonged to different clones, the most frequent being ST8.ConclusionsIn an area of Italy with high density of pig farming, LA-MRSA is able to colonize the population and rarely to produce infections. Typical CA-MRSA is more common than LA-MRSA among CAI.

Antibiotic resistance patterns of methicillin-resistant Staphylococcus aureus (MRSA) isolated from livestock and associated farmers in Anuradhapura, Sri Lanka

“…The study showed that the MRSA prevalence among livestock was 13.8% (pigs: 25.8%, poultry: 9.3% and cattle: 6.2%) which is lower when compared with European countries, where the percentage in Germany and Netherlands was >35% 22,23 and in Poland 20.6%. 24 However, some Asian countries exhibit lower carriage of MRSA in livestock as is the case in China: 11.4%, 25 Korea: 3.2%, 22 Malaysia: 1.4%, 24 Japan: 0.9%, 29 and Taiwan: 14.4%. 26 In our study, MRSA carriage among livestock farmers was 15.9% (piggery: 25.8% poultry: 12.5% and cattle: 9.6%).…”

“…13 Similar to livestock, the livestock farmer's MRSA carriage also showed low prevalence compared to Europe and the USA. [21][22][23][24][25][26] But the Sri Lankan prevalence is higher than that of other Asian countries, which report …”

Eradication of Methicillin-Resistant Staphylococcus aureus and of Enterobacteriaceae Expressing Extended-Spectrum Beta-Lactamases on a Model Pig Farm

“…Farmers are confronted with two different consequences of this problem: the potential danger of animal colonization with drug-resistant bacteria for (i) humans living on or in the vicinity of farms (11)(12)(13) and for (ii) consumers of animal products (14)(15)(16)(17)(18). Indeed, livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) have been found in humans living and working in close contact with pigs and also in hospitals in rural areas (11,(19)(20)(21)(22)(23)(24)(25). In contrast, ESBL-E could possibly be transferred from animals to humans via meat products (16,(26)(27)(28).…”

Gram-positive bacterial resistant strains of interest in animal and public health

“…Molecular characterization revealed that the isolated clones are grouped in the complex 398 (CC398), called livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA). LA-MRSA has been shown with pathogenic to humans and can cause serious infections such as endocarditis and pneumonia (REISCHL et al, 2009;MONACO et al, 2013).…”