EPIDEMIOLOGY First Report on Vancomycin-Resistant Staphylococcus aureus in Bovine and Caprine Milk Debaraj Bhattacharyya, 1 Jaydeep Banerjee, 1 Samiran Bandyopadhyay, 1 Bimalendu Mondal, 1 Pramod K. Nanda, 1 Indranil Samanta, 2 Achintya Mahanti, 2 Arun K. Das, 1 Gunjan Das, 3 Premanshu Dandapat, 1 and Subhasish Bandyopadhyay 1 The present investigation was carried out to study the vancomycin resistance pattern of Staphylococcus aureus isolates (n = 274) obtained from 352 milk samples of bovine (269) and caprine (63) clinical and subclinical mastitis from different districts of West Bengal, India. Of them, seven isolates (vancomycin-resistant S. aureus [VRSA] 1–7) exhibited resistance to vancomycin. Minimum inhibitory concentration of vancomycin (MIC van ) for VRSA2 and VRSA3 was ‡16 mg/ml; thus categorized as VRSA. For rest of the isolates, MIC van was 8 mg/ml and they were grouped as vancomycin intermediate S. aureus (VISA). Even though all the isolates were resistant to cefoxitin and oxacillin and possessed mecA gene, none of them carried vancomycin resistance gene. Furthermore, all the seven isolates were subjected to Staphylococcal cassette chromosome mec (SCCmec) typing, Staphylococcal protein A (spa) typing, and enterobacterial repetitive intergenic consensus polymerase chain reaction. All the isolates except VRSA3 and VRSA4 from Kolkata district exhibited diverse genetic lineage, irrespective of their host and antibiotic resistance pattern. These two isolates showed clonal similarity (MRSA-SCCmec-V-spa t267) with methicillin-resistant S. aureus (MRSA) strains previously reported in human and animal infection. Isolation of VRSA and VISA could probably be due to intensive use of vanco- mycin in healthcare premises, which might have led to the development of glycopeptide-resistant strains and thereafter, further disseminated in the environment, including livestock farms. Detection of VRSA in milk is a serious concern as it may further cause health problems in the consumers. This is the first ever report of VRSA in food animals, even though the pathogen is otherwise prevalent in humans. Introduction S taphylococcus aureus is responsible for a wide spectrum of diseases, including pyoderma, osteomyelitis, endocarditis, septicemia, surgical wound complications, pneumonia in human beings, and mastitis in diary animals. 1,2 With the emergence of methicillin-resistant S. aureus (MRSA) and its increasing resistance to antibiotics of various groups such as penicillins, cephalosporins, fluoroquinolones, ami- noglycosides and macrolides, vancomycin has been the anti- biotic of the last resort to treat the hospitalized patients critically infected with MRSA or other Gram-positive organ- isms like Clostridium difficile. 3,4 Vancomycin is a glycopeptide antibiotic, which acts against Gram-positive bacteria by inhibition of cell wall synthesis. However, intensive use of vancomycin over the years in healthcare premises has eventually led to the devel- opment of glycopeptide-resistant strains of S. aureus. After its first report during 1997 in Japan, vancomycin-resistant S. aureus (VRSA) and vancomycin intermediate S. aureus (VISA) were reported from various countries, including United States, 5 United Kingdom, 6,7 Germany, 8 Portugal, 9 Brazil, 10 China, 11 Bangladesh, 12 and Jordan. 13 Most of these reports were concerned with hospitalized human patients with preexisting MRSA infection. In contrast, there is hardly any report available on the oc- currence of VRSA in animals possibly due to the fact that glycopeptides are not regularly used in veterinary practices. Nevertheless, contamination of the environment or pasture land situated in and around the human healthcare premises with VRSA and its further colonization in the domestic ani- mals cannot be ruled out. In recent past, VRSA isolates of farm animal origin have been reported from South Africa. 14 Again, this group of workers have reported reduced vancomycin 1 ICAR-Indian Veterinary Research Institute, Eastern Regional Station, Kolkata, India. 2 Department of Veterinary Microbiology, WBUAFS, Kolkata, India. 3 College of Veterinary Sciences & A.H, CAU, Aizawl, India. MICROBIAL DRUG RESISTANCE Volume 00, Number 00, 2016 ª Mary Ann Liebert, Inc. DOI: 10.1089/mdr.2015.0330 1