Effects of Reducing Antimicrobial Use and Applying a Cleaning and Disinfection Program in Veal Calf Farming: Experiences from an Intervention Study to Control Livestock-Associated MRSA

• Published in: PloS one 2015-08, Vol.10 (8), p.e0135826
• Main Authors: Dorado-García, Alejandro, Graveland, Haitske, Bos, Marian E H, Verstappen, Koen M, Van Cleef, Brigitte A G L, Kluytmans, Jan A J W, Wagenaar, Jaap A, Heederik, Dick J J
• Format: Article
• Language: English
• Subjects: Agriculture; Animals; Anti-Infective Agents - adverse effects; Anti-Infective Agents - therapeutic use; Antibiotics; Antiinfectives and antibacterials; Antimicrobial agents; Calves; Cattle; Centraal Veterinair Instituut; Central Veterinary Institute; Cleaning; CVI Infectiebiologie; CVI Infection Biology; Disease control; Disinfection; Disinfection & disinfectants; Drug resistance; Epidemiology; Family farms; Farm buildings; Farmers; Farming; Farms; Humans; Immunology; Infectiebiologie; Infection Biology; Infectious diseases; Intervention; Laboratories; Landbouwhogeschool Wageningen; Livestock; Methicillin; Methicillin-Resistant Staphylococcus aureus - drug effects; Methicillin-Resistant Staphylococcus aureus - pathogenicity; Public health; Risk assessment; Risk Factors; Staphylococcal Infections - drug therapy; Staphylococcal Infections - epidemiology; Staphylococcal Infections - microbiology; Staphylococcus aureus; Staphylococcus infections; Trends; Veal; Veterinary medicine; Wageningen Bioveterinary Research
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0135826

With the ultimate aim of containing the emergence of resistant bacteria, a Dutch policy was set in place in 2010 promoting a reduction of antimicrobial use (AMU) in food-producing animals. In this context, a study evaluated strategies to curb livestock-associated methicillin resistant Staphylococcus aureus (LA-MRSA). Fifty-one veal calf farms were assigned to one of 3 study arms: RAB farms reducing antimicrobials by protocol; RAB-CD farms reducing antimicrobials by protocol and applying a cleaning and disinfection program; and Control farms without interventions. MRSA carriage was tested in week 0 and week 12 of 2 consecutive production cycles in farmers, family members and veal calves. Interventions were validated and a cyclic rise in MRSA-prevalence in animals was shown with a more moderate increase in RAB farms. Prevalence in humans declined parallel over time in the study arms but RAB farms were at the lowest MRSA levels from the beginning of the study. In RAB-CD farms, human and animal prevalence did not differ from Control farms and MRSA air loads were significantly higher than in the other study arms. Mimicking the national trend, an overall AMU decrease (daily dosages per animal per cycle (DDDA/C)) was observed over 4 pre-study and the 2 study cycles; this trend did not have a significant effect on a set of evaluated farm technical parameters. AMU was positively associated with MRSA across study arms (ORs per 10 DDDA/C increase = 1.26 for both humans (p = 0.07) and animals (p = 0.12 in first cycle)). These results suggest that AMU reduction might be a good strategy for curbing MRSA in veal calf farming, however the specific cleaning and disinfecting program in RAB-CD farms was not effective. The drop in MRSA prevalence in people during the study could be attributed to the observed long-term AMU decreasing trend.