Aim:The study was carried out with the aim to identify the suitability of the milk for consumer use with special reference to Staphylococcus aureus from milk samples collected from various local vendors and determine the antibiotic susceptibility pattern of those positive isolates.Materials and Methods:A total of 110 milk samples were collected from the local milk vendors in and around Tirupathi region of India. All the samples were enriched with buffered peptone water in 9:1 ratio and the then inoculated on baird parker agar medium with added 2% egg yolk tellurite emulsion as selective medium for S. aureus and confirmed with mannitol salt agar, Gram’s staining and biochemical tests. The typical cultural characters with coagulase-positive samples were taken as positive samples the positive samples were tested for antibiotic susceptibility with 10 different antibiotics by employing disc diffusion method.Results:Prevalence of coagulase-positive S. aureus was 39.09% (43/110) from the milk samples. The antibiotic susceptibility test of positive isolates showed high resistant toward penicillin G 37/43 (86.04%) and ampicillin 32/43 (74.42%), and also showed resistant to methicillin 6/43 (13.95%), cephalothin 6/43 (13.95%), tetracycline 6/43 (13.95%), ciprofloxacin 4/43 (9.30%), enrofloxacin 3/43 (6.97%), cefoxitin 2/43 (4.65%), gentamicin 2/43 (4.65%), and co-trimoxazole 2/43 (4.65%). Many individual isolates showed resistant against two or more antibiotics in our study.Conclusion:The above study results show that the milk samples collected from local vendor having S. aureus, which can induce disease condition as well as antibiotic resistant to the humans particularly young children and old age peoples by means of consumption of raw milk and its products. This is the public health issue, which needs to be solved by educating the local vendors regarding health problems related to unhygienic milk supply and make the awareness among the consumers about this hazards and preventive measures.

Salmonella enterica serovar Typhimurium (S. Typhimurium) is a common serovar associated with non-typhoidal salmonellosis globally. However, there is insufficient data on molecular characterization of S. Typhimurium isolates from India. This study was undertaken to determine the antimicrobial resistance (AMR), plasmid, virulence profiles and molecular subtypes of S. Typhimurium Indian isolates (n = 70) of clinical and environmental origin isolated during 2010–2017. Antimicrobial susceptibility and minimum inhibitory concentrations were determined by disc diffusion and E-test methods respectively. Plasmid extraction was done following standard protocol. AMR genes, virulence genes and plasmid incompatibility types were detected by PCR; Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) were used for molecular subtyping. Majority (57%) of the study isolates was pan susceptible; five AMR profiles were observed among the resistant (43%) isolates. AMR was significantly (p = 0.004) associated with extra-intestinal isolates than intestinal isolates.The class 1 integron and plasmid-mediated quinolone resistance genes (qnrB1, qnrS1) in the resistant isolates were transferable by conjugation. Plasmids (≥1) ranging from 1.9 to 254kb size and of IncFIIS and/or FIB type were found in most isolates. A total of 39 pulsotypes by PFGE and four sequence types by MLST like ST36 (55.7%), ST19 (32.9%), ST313 (10%) and ST213 (1.4%) were observed. ST36 and ST19 were found circulating in both clinical and environmental host, while ST313 isolates had an exclusive clinical origin. All ST19 isolates (100%) were drug-resistant, while isolates belonging to ST313 (100%), ST213 (100%) and ST36 (82%) were pan susceptible. The virulence plasmid (VP) genes (spvB- spvC) were present in all genotypes except ST36. The VP was significantly (p<0.001) associated with extra-intestinal than intestinal isolates. Some environmental and clinical isolates were clonal indicating their zoonotic transmission. Knowledge on the molecular subtypes and AMR profiles of locally prevalent Salmonella serotypes is important for effective control of spread of resistant organisms. The MLST of S. Typhimurium isolates and its association with AMR, virulence profiles was not reported earlier from India.

Objective: Non-typhoidal Salmonella (NTS) is a major foodborne pathogen in both developed and developing countries. The study was undertaken to determine the prevalence, serotype distribution and antimicrobial resistance profiles of NTS isolates from livestock and food samples collected in and around Kolkata during 2012-2013. Materials and methods:A total of 500 samples (animal, poultry and raw food) from 12 different places randomly collected in and around Kolkata were processed as per standard procedures and analyzed for NTS. Serotyping of the isolates was done followed by determination of antimicrobial resistance profiles and Minimum inhibitory concentrations following disc diffusion and E-test methods.Results: A total of 53 (10.6%) NTS isolates were recovered, with highest isolation from chicken (40%), followed by beef and poultry cloacal samples (22% each). Total 11 Salmonella serovars were identified with predominance of Salmonella enterica serovar Typhimurium (S. Typhimurium) (30.2%) followed by S. Kentucky (22.6%), S. Idikan (15.1%) and other serovars. This is the first report of isolation of S. Idikan from India. Thirty-two (60.4%) isolates were pan susceptible to all drugs tested. Percentage distribution of resistant NTS against antimicrobials were: nalidixic acid (24.5%), ampicillin (17%), amoxicillin (17%), streptomycin (15.1%), tetracycline (11.3%), chloramphenicol (9.4%), co-trimoxazole (9.4%) and ciprofloxacin (5.7%). Only one isolate (S. Senftenberg) was resistant to both fluroquinolones and third generation cephalosporins. Multidrug resistance (≥3 classes of antimicrobials) was observed in 13.2% NTS isolates. Conclusion:High prevalence of NTS in poultry and meat samples in Kolkata poses a potential risk of foodborne disease in humans. J Microbiol Infect Dis 2016;6(3): 113-120