The emergence of LA-MRSA in major food animal species has raised numerous questions and concerns for public health and livestock industries. First identified in The Netherlands around 2004, these organisms have since been found in swine herds in many European countries and also in North America [10], [11], [15]. Based on screening using farm dust samples, the prevalence of positive swine herds varied widely among European countries, from 0% in England, Ireland and Sweden, to over 41% in Germany and 51% in Spain [16]. As found in our study, within positive herds, prevalence of culture positive pigs is typically high (17% to 100% of pigs positive). Initial studies in North America indicated that the prevalence of LA-MRSA in swine may be similar to that reported in Europe. In a convenience sample of 20 herds in Ontario, Khanna et al (2008) found 25% of 285 pigs and 20% (5 of 25) of swine farm workers were culture positive, with spa type t034 predominant [11]. Smith et al (2009) first documented the presence of LA-MRSA in the USA in one of two swine production systems studied, and found a high within-herd prevalence (70% of pigs) in the positive system [10]. Davies et al (in preparation) found LA-MRSA occurring in US swine veterinarians (5%) and in 25% of 539 market hogs from 45 herds slaughtered at major US packing plants, with t034 again being the most common spa type. Given the narrow scope of the study of Smith et al (2009) and the difficulty in interpreting data from market hogs due to the possibility of exposure during transport and lairage, further studies are required to obtain more reliable estimates of the prevalence of MRSA in US livestock industries.