• Prof. dr. J.A. Wagenaar, Department of Infectious diseases and Immunology
• Prof. dr. ir. J.A.P. Heesterbeek, Department of farm animal health

• Institute for Risk Assessement Sciences
• Ministry of Agriculture, Nature and Food Quality
• Product Boards for Livestock, Meat, and Eggs

The main aim of the MRSA study in veal farming is to assess prevalence and risk factors associated with MRSA colonization in veal farmers and veal calves. The study consists of four sub studies. Sub study I focuses mainly on the prevalence and associated health risk factors of MRSA colonization in human and veal calves. The objective of sub study II and II is to gain more insight in the spread and dynamics of MRSA colonization in human and animal respectively. The aim of sub study IV is to assess the environmental risk factors / exposure associated with MRSA colonization in animal and human.

Sub study I is a cross sectional study among 400 veal farmers, family members and employers. A questionnaire will be filled out and a nasal swabs is taken to determine MRSA colonization. In addition also a farm specific questionnaire is filled out and nasal swabs are taken from a selection of the calves on the farm.

Sub study II an III are longitudinal studies in human and veal calves respectively. Sub study II investigated the spread and dynamics of MRSA colonization in human, during different levels of animal contact. Repeatedly, nasal- and throat swabs will be taken by 150 participants. Questionnaires will be filled out to determine the duration of animal contact and risk factors.

Sub study III focuses on dynamic of MRSA in veal calves. To gain more insight in de variation of MRSA carrier ship over time in veal calves, first a pilot study is performed. Subsequently, based on the results of the risk factor analysis of the cross- sectional and the results of the pilot study an elaborate study will be done, including interventions.

Methicillin-resistant Stahylococcus aureus (MRSA) is a bacteria resistant for all β-lactam antibiotics and previously mainly found in hospital settings. During the past decades, the prevalence of Methicillin Resistant Staphylococcus aureus (MRSA) in clinical isolates in The Netherlands is one of the lowest in Europe (<1%) . This low prevalence can be best explained by the national "Search and Destroy" policy which demands isolation and screening of patients at risk for MRSA carriage on admission to healthcare facilities.

Recently, a specific MRSA clone has been reported at unexpected high prevalence among pig farmers and veterinarians in the Netherlands, and a case control study showed that pig and cattle farmers have an increased risk for being MRSA positive. The source of these human infections can be found in the pig population and veal calves.

Since the emergence of community-acquired and animal related MRSA, the number of reports on MRSA in animals and on animal to human transmission of MRSA has been rapidly rising.

Because MRSA infections cause increased mortality, morbidity and health-care expenditure both in hospital and community settings a low prevalence of MRSA is desirable. Since people in close contact with veal calves are at high risk of MRSA colonization the "search and destroy" policy is adapted which involves a considerable increase of costs. For this reason, studies which investigate risk factors associated with MRSA colonization in human and animal and this high risk population is extremely useful.

Risk factors for MRSA in the pork production chain (BACTOPATH)