Tuesday, 1 May 2012

Human MRSA st398 carriage linked to the live pigs in slaughterhouse

The Dutch in the lead again with Britain absent from pig MRSA research. 

Britain does not have MRSA in its pigs or pork, because Britain's government veterinarians did not want to find it and did not look properly. They only looked when the EU forced their hand, took a few dust samples and said "nothing found."

Britain's pigs were declared free of MRSA.

Pretty well every other civilised country has found a growing human health risk from MRSA in pigs, but not Britain.

Sooner or later they are going to have to own up. Then the questions over their extraordinary misbehaviour, going back the triple epidemics of circovirus, CSF and FMD will flood in. 

They don’t have any sensible answers.

Abstract of BMJ paper here

Occup Environ Med doi:10.1136/oemed-2011-100069
·         Exposure assessment
·         Original article

Livestock-associated MRSA ST398 carriage in pig slaughterhouse workers related to quantitative environmental exposure

1.     Maarten J Gilbert1, 
2.     Marian E H Bos1, 
3.     Birgitta Duim2, 
4.     Bert A P Urlings3,4, 
5.     Lourens Heres3,
6.     Jaap A Wagenaar2,5, 
7.     Dick J J Heederik1,6
+Author Affiliations
1.        1Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
2.        2Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
3.        3VION Food Group, Eindhoven, The Netherlands
4.        4Animal Sciences Group, Wageningen University, Wageningen, The Netherlands
5.        5Central Veterinary Institute, Wageningen UR, Lelystad, The Netherlands
6.        6Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
1.     Correspondence toDr Marian E H Bos, Institute for Risk Assessment Sciences (IRAS), Utrecht University, PO BOX 80178, 3508 TD Utrecht, The Netherlands; m.e.h......nl
1.      Contributors MJG, MEHB, BAPU, LH, JAW and DJJH were involved in conception and design of the study. MJG, MEHB and LH collected the samples and data. MJG, MEHB and DJJH cleaned and statistically analysed the data. MJG, MEHB, BD, JAW and DJJH interpreted the data. MJG and MEHB performed laboratory analyses. BD and JAW developed real-time PCR targeting ST398. MJG, MEHB, BD, JAW and DJJH interpreted the results of the laboratory analysis. MJG, MEHB, JAW and DJJH drafted the paper. MJG, MEHB, BD, BAPU, LH, JAW and DJJH revised the draft paper.
·         Accepted 8 March 2012
·         Published Online First 27 April 2012


Objectives To assess livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) carriage among workers in pig slaughterhouses and assess associated risk factors, including occupational exposure to LA-MRSA.
Methods A cross-sectional study in three Dutch pig slaughterhouses was undertaken. Nasal swabs of participants were taken. Nasal swabs and surface wipes, air and glove samples were screened for presence of methicillin-resistant Staphylococcus aureus (MRSA). MRSA was quantitatively determined on gloves and in air samples by culturing and real-time PCR.
Results 11 of 341 (3.2%) participants were identified as nasal MRSA carriers. MRSA-positive workers were predominantly found at the start of the slaughter process. Major risk factors for carriage were working in the lairage and working in the scalding and dehairing area. Most nasal isolates (73%) belonged to the LA-MRSA clone ST398. MRSA ST398-positive environmental samples were found throughout the slaughter process. A clear decrease was seen along the slaughterline in the number of MRSA-positive samples and in the MRSA amount per sample.
Conclusions This study showed that working in the lairage area or scalding and dehairing area were the major risk factors for MRSA carriage in pig slaughterhouse workers, while the overall prevalence of MRSA carriage is low. Occupational exposure to MRSA decreased along the slaughterline, and the risk of carriage showed a parallel decrease.