Background and Aim: Nanosized inorganic antibacterial materials have received increasing attention in recent years. The present study aimed to determine the antimicrobial activity of silver (Ag) and zinc oxide (ZnO) nanoparticles alone and in combination with antibiotics against reference strains of pathogenic microorganisms as Staphylococcus aureus (Staph. aureus), Salmonella enterica subsp. Bukuru, Escherichia coli (E.coli) and Candida albicans ( C. albicans). Methods: The antimicrobial effect of metal-nanoparticles (AgNPs and ZnONPS) and in combination with antibiotics was studied using the normal disc-diffusion method. Results: Both AgNPs and ZnONPs had increased antibacterial activity with an increase in their concentration against Gram-positive bacterium (Staph. aureus), Gram-negative bacteria (E. coli and Salmonella spp) and no effect on C. albicans. The synergistic effect of antibiotics (azithromycin, cefotaxime, cefuroxime, fosfomycin and chloramphenicol) against E. coli was significantly increased in the presence of AgNPs compared to antibiotic only. However, all antibiotics had a synergistic effect in the presence of AgNps against Salmonella spp. On the other hand, the antibacterial action of AgNPs with oxacillin and neomycin antibiotics against Staph. aureus was significantly decreased in comparison with antibiotics only. The synergistic effect of antibiotics (azithromycin, oxacillin, cefotaxime, cefuroxime, fosfomycin and oxytetracycline) against E. coli was significantly increased in presence of ZnONPs compared to antibiotic only and also the synergistic effect of antibiotics (azithromycin, cefotaxime, cefuroxime, fosfomycin, chloramphenicol and oxytetracycline) against Staph. aureus was significantly increased in the presence of ZnONPs compared to antibiotics only. On the other hand, most antibiotics had an antagonistic effect in presence of ZnONps against Salmonella spp. Conclusion: AgNPs and ZnONPs demonstrate a good synergistic effect with antibiotics and this may open the door for a future combination therapy against pathogenic bacteria.

World Health Organization classified Listeria monocytogenes as a major notable foodborne pathogen associated with high mortality and hospitalization. The study reports the prevalence, antibiogram, virulence determination and genetic characterization of L. monocytogenes from different food products. A total of 250 food samples, fifty samples each from raw milk, ice cream, minced meat, fish fillet and sausage were collected from the Menoufiya governorate in Egypt. L. monocytogenes was detected in 17 (6.8%) of the tested food samples including minced meat (14%), fish fillet (8%), sausage (6%) and raw milk (6%). The antimicrobial susceptibility assay of 17 L. monocytogenes isolates against seventeen antibiotics belonging to eight antibiotics classes revealed a high susceptibility to norfloxacin (82.3%), amoxicillin-clavulanic acid (76.4%), cefotaxime (70.5%), erythromycin (64.6%), amoxicillin (64.6%), gentamicin (58.7%) and vancomycin (58.7%). While, high resistance was observed against oxytetracycline (76.4%), trimethoprim-sulfamethoxazole (76.4%), chloramphenicol (70.5%), doxycycline (64.6%), levofloxacin (41.2%) and azithromycin (41.2%). Of note, all L. monocytogenes isolates were multidrug-resistant. The multiplex PCR successfully amplified L. monocytogenes in all tested isolates. Screening of the five virulence-related genes revealed the hlyA and iap as the most prevalent genes followed by actA gene, however, the inlA and prfA genes were not detected in any of the studied isolates. The partial 16S rRNA gene sequencing of three L. monocytogenes isolates showed a high nucleotide similarity (99.1–99.8%) between the study isolates and various global clones, and phylogenetic analysis clustered these L. monocytogenes strains with other Listeria species including L. welshimeri, L. seeligeri and L. innocua. This study demonstrates the impact of L. monocytogenes as a major contaminant of various food products and suggests more attention to the awareness and hygienic measures in the food industry.

Parasitic diseases are a multi-problem that affects animal productivity, public health and economy. A total of 45,094 animals slaughtered over three years in Elmahalla Elkubra slaughterhouse, Gharbia, Egypt were surveyed to determine the prevalence of Fascioliasis, Cysticercosis and Hydatidosis. Economic losses associated with Fascioliasis were estimated as well. The overall prevalences of Fascioliasis and Cysticercosis were 0.2% and 0.6%, respectively. Hydatidosis was not found in any of the examined animal species. The highest rates of Cysticercosis and Fascioliasis prevalences were reported in sheep (1.2%, 0.41%), followed by cows (0.44%, 0.14%) and lastly buffaloes (0.13%, 0.07%), respectively. Pattern of the parasitic diseases over three years showed a significant increase in sheep Cysticercosis and significant decrease in cows Cysticercosis, sheep Fascioliasis and cows Fascioliasis. The total economic losses due to Fascioliasis in terms of liver condemnations and carcasses weight losses over the three years of study was estimated as 106,331.3 EGP (16,800.4 USD). This study highlights the impact of these parasitic diseases in the study region and may eventually stimulate better efforts towards the control and possible eradication of these parasitic zoonosis in Egypt.

This study highlights the possible emergence of Salmonella subspecies salamae with zoonotic potential.

Food poisoning caused by Staphylococcus aureus ( S. aureus ) toxins is considered one of the foremost public health threat that usually occurs through the ingestion of raw milk contaminated with staphylococcal enterotoxins. The current study spotlights on the prevalence, antibiogram and genetic diversity of S. aureus enterotoxin genes. One hundred and fifty of raw milk (90) and ice cream (60) samples were randomly collected from local markets from Sadat city, Egypt . S. aureus was recovered from 44% of raw milk and 20% of ice cream samples. The identification for the obtained S. aureus isolates was confirmed through targeting the nuc gene. Antibiogram pattern of 32 S. aureus isolates showed high resistance to Cefoxitin, Sulpha/Trimethoprim, Tetracycline, Norfloxacin, Penicillin and Cephradine. However, high susceptibility to Gentamycin and Vancomycin were observed. Multiplex PCR was a competent practise for the recognition of Staphylococcus enterotoxin (SE) genes ( SEA , SEB and SED ). The phylogenetic analysis of the SED gene of enterotoxigenic S. aureus strains showed identical similarity with 100% to each other and high similarity with other international isolates in GenBank from different localities and sources. The frequency of enterotoxigenic S. aureus strains in milk products could have serious hazardous effects on humans. These results suggested possible strains transmission between different geographical areas through the food and milk product trades.