Globalisation, climate change, changes in eating habits and the food industry, modern animal husbandry and market demands often have a negative impact on quality assurance, food safety and animal health. After the eradication of some zoonotic diseases that previously often jeopardized the human population, today in developed countries, the focus is mainly on the control of zoonoses transmitted by food. Salmonella is one of the most common pathogens that can be transmitted from animals to humans, and its reservoirs are poultry, cattle and pigs, so one transmission route to humans is from contaminated food of animal origin. Multidrug-resistant isolates of Salmonella, which can transfer their resistance genes to other microorganisms, are considered a serious threat to public health. Control of Salmonella primarily depends on a good monitoring system and knowledge of the presence of serovars and strains in an epizootiological area. During the first nine months of 2016, 1321 samples of poultry meat and products were examined, among which 108 harboured Salmonella. Altogether, 29 of the 108 isolates (26.85%) were Salmonella Infantis. For all 29 S. Infantis isolates, antimicrobial resistance was tested by the disc diffusion method. The isolates showed 100% resistance to amoxicillin, and nalidixic acid.

The subject of this study was the examination of the chemical composition and antimicrobial activity of peppermint oil (Menthae piperitae L.), that was produced from the plant collected from the plantation in the city of Banja Luka. To examine the chemical composition of the Mentha piperita essential oil we used the GC-FID method. On it’s chromatogram it was clearly shown that the main components of the oil were menthole with the content of 43.66%, menthone 20.02%, iso-menthone 7.73%, following by 1,8-cineole with a percentage of 6.49% and menthil-acetate with 3.31%. The content of the previously mentioned components were all in accordance with the suggestions made by Ph.Eur 8.0. For the purpose of examination antimicrobial activity of the peppermint oil we used agar diffusion method. The results have shown that etheric oil of Menthae piperitae reflects very good antimicrobial activity on all bacterial cultures that we used in this study. The inhibiton zones moved from 12 mm for Pseudomonas aeruginosa to 37.66 mm for Staphylococcus aureus. Such an outcome of our study, and many others from all around the world, indicates the future potential use of peppermint oil in the treatment of bacterial infections, maybe even lowering the use of antibiotics.

European Centre for Disease Prevention and Control (ECDC) and World Health Organization (WHO) initiate public awareness campaign about antimicrobial substances and their rational uses due to the increasing prevalence of multidrug resistant strains of bacteria. The objective of this study was to evaluate antimicrobial activity of Hypericum perforatum essential oil and reference antimicrobial drugs against the growth of certain bacteria Staphylococcus aureus, Salmonella typhimurium i Pseudomonas aeruginosa.

Health-safe water is the basis of a healthy life and is one of the priorities in primary health care. Water safety involves microbiological, physicochemical and radiologically clean water, a sufficient amount of water and continuous delivery. Due to the great epidemiological importance of water, whose impact is immediate and through which various infectious diseases can be transmitted harmful and dangerous chemicals can be introduced, it is necessary, in order to protect human health, to control the safety of drinking water. The aim of this study was to determine the microbiological safety of water used for watering animals, as well as in the food industry. Based on data collected from year 2015 to 2017, 26.20% water samples did not meet requirements defined by Regulation on hygienic quality of drinking water. The greatest number of samples was unsatisfactory due to an increased number of microorganisms at the temperatures of 22°C (63.40%) and 37°C (54.90%), and when it comes to pathogenic microorganisms due to the presence of intestinal enterococci (58.80%). The lowest risk of the presence of coliforms and E. coli is in the water from the water supplying network, while it's much higher presence is in wells and in the water from the wellspring. The presence of intestinal enterococci is significant in all three types of drinking water, while the presence of sulphite-reducing clostridia was observed only in the wellspring water.

Uncontrolled use of antimicrobials in the prophylaxis and treatment of human and animal diseases leads to the appearance of residues in the environment and food. The use of antimicrobials as growth promoters in breeding affirms the importance of their residual finding in foods of animal origin. Bacteria of the genus Salmonella are one of the most common causes of food poisoning. All species of this genus are pathogenic to humans and cause various diseases known as salmonellosis. Humans can become infected through the faecal-oral route by consuming contaminated food and water or by direct contact with an animal. Salmonella that are resistant to antimicrobial drugs can transfer resistance genes to other microorganisms. In this work, the resistance of 10 Salmonella isolates from poultry meat to 8 different antimicrobial substances was examined by the disk diffusion method. All Salmonella isolates were sensitive to trimethoprim-sulfamethoxazole and chloramphenicol. All isolates were resistant to amoxicillin and significant percentages were resistant to other antimicrobial drugs. Also, multi-drug resistance of Salmonella isolates was found. The best prevention of salmonellosis in humans is constant and comprehensive control of this hazard in food products during production, processing, storage, and sale.

Food contact surfaces can be a source of food contamination. Bacteria of the genus Proteus are known as opportunistic pathogens, often associated with faecal contamination and decomposition of organic matter. This study aimed to isolate Proteus spp. from surface samples (of dimensions 5 cm² × 5 cm²). Three levels of artificially soiled aluminium foil were prepared using bacterial suspensions of Proteus hauseri ATCC 13315. Afterwards, the surface swabbing method for the detection of Proteus spp. was applied. The swab was homogenised with Eugon LT 100 broth, and 1 mL was transferred to the enrichment broth. After the incubation of the enrichment broth, streaking on the Brilliant Green Agar and Salmonella Shigella Agar was performed. The characteristic colonies were confirmed by biochemical reactions. The number of positive findings of Proteus hauseri on the applied level of contamination was used for calculation by the PODLOD_ver12.xls ECEL program by Wilrich and Wilrich. This program estimates the probability of detection (POD) function and the limit of detection (LOD) of qualitative microbiological methods. The results of the detection of Proteus hauseri in surface samples showed LOD₅₀ = 24.60 [48.96; 97.45] CFU in 1 mL of swab rinse, and LOD₉₅ = 106.30 [211.59; 421.15] CFU in 1 mL of swab rinse. The applied method for isolation of Proteus spp. from the surface samples can be used for well-contaminated surfaces.