LA-MRSA in broiler flocks

LA-MRSA is the acronym for "Livestock-associated MRSA", where MRSA stands for methicillin-resistant Staphylococcus aureus, a species of MRSA that is associated with conventional animal fattening. This includes humans in close working contact with these animals (especially pigs, but also cattle for fattening and poultry for fattening) (Layer et al. 2012). In horse husbandry, for example, it is primarily CA-MRSA that appear to be a problem.

The reports on the isolation of MRSA in poultry refer essentially to the foodstuff poultry. Retrospective investigations of ninety Belgian S. aureus isolates from 1970 to 1972 failed to detect MRSA. However, in Korea, the detection of three MRSA isolates in the period from 2001 to 2003 (one poultry meat sample and two bale lesions) was successful (Lee 2003). On-farm investigations in Belgium revealed for the first time the presence of MRSA in healthy poultry. The extent was ten MRSA-positive isolates from sampling of five farms (rate 12.3 %; n=39). They all belonged to type ST398 and spa types t011, t567, and SCCmec types III, Iva and V. In the Netherlands, a study of chickens delivered to the slaughterhouse concluded that 7% of all birds had to be considered MRSA positive (Mulders et al. 2010). The commercial poultry that appear to be more affected by MRSA compared to chickens are turkeys. For example, in a study investigating turkey fattening farms, the prevalence is 90% (n=20) and that of individuals living on the farms is over 37% (n=59). Both animals and ambient dust samples from the housing facilities tested positive, almost exclusively MLST CC398 of spa types t011 (83.2 % of avian isolates; 90.2 % of human isolates), t1456, t034 and t2330 were present (Richter et al. 2012).

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