Jan. 21, 2013 - LA-MRSA Detected in Milk from UK Dairy Cows

According to a study published in Eurosurveillance, researchers have isolated livestock-associated, methicillin-resistant Staphylococcus aureus (LA-MRSA)from bulk tank milk from 5 different farms in the UK. This is the first time this organism has been isolated in the UK. Although it is thought that pasteurization prevents entry of LA-MRSA into the food chain they warn that individuals with regular contact with dairy cows are likely to have a higher risk of infection with the germ than the general population.

In Illinois and Iowa, nasal samples from swine and their handlers showed that 45% to 49%, were colonized with LA-MRSA but no actual infections from that source have been found in the US.
See the abstracts below for more information, or visit the original links, Here and Here.

First detection of livestock-associated meticillin-resistant Staphylococcus aureus CC398 in bulk tank milk in the United Kingdom, January to July 2012

Livestock-associated meticillin-resistant Staphylococcus aureus belonging to clonal complex 398 (LA-MRSA CC398) is an important cause of zoonotic infections in several countries, but there is only a single published report of this lineage from the United Kingdom (UK). Here, we describe the isolation of LA-MRSA CC398 from bulk tank milk from five geographically dispersed farms in the UK. Our findings suggest that LA-MRSA CC398 is established in livestock in the UK. Awareness of the potential occupational risks and surveillance in other food-producing animal species should be promoted.

Livestock-associated Methicillin-Resistant Staphylococcus aureus Sequence Type 398 in Humans, Canada

Rates of colonization with livestock-associated methicillin-resistant Staphylococcus aureus (MRSA) sequence type 398 have been high for pigs and pig farmers in Canada, but prevalence rates for the general human population are unknown. In this study, 5 LA-MRSA isolates, 4 of which were obtained from skin and soft tissue infections, were identified from 3,687 tested MRSA isolates from persons in Manitoba and Saskatchewan, Canada. Further molecular characterization determined that these isolates all contained staphylococcal cassette chromosome (SCC) mecV, were negative for Panton-Valentine leukocidin, and were closely related by macrorestriction analysis with the restriction enzyme Cfr91. The complete DNA sequence of the SCCmec region from the isolate showed a novel subtype of SCCmecV harboring clustered regularly interspaced short palindromic repeats and associated genes. Although prevalence of livestock-associated MRSA seems to be low for the general population in Canada, recent emergence of infections resulting from this strain is of public health concern.

Read More Here