Prevalence of EnterotoxigenicStaphylococcus aureusand Shiga Toxin ProducingEscherichia coliin Fish in Egypt: Quality Parameters and Public Health Hazard

Abstract

This study investigated the prevalence of Staphylococcus aureus enterotoxin genes and shiga toxin -producing Escherichia coli (STEC) in fish and evaluated quality parameters of examined fish. A total of 150 fish samples belonging to 6 species (25/each species) were cultured on Baird-Parker agar and eosin methylene blue agar. Staphylococcal enterotoxin genes and virulence genes (stx1, stx2, and eaeA genes) in E. coli serotypes were determined by multiplex PCR. Aerobic plate count (APC), Enterobacteriaceae count, coliform count, and Pseudomonas count were performed. Also, levels of total volatile base nitrogen and histamine in fish were determined. The prevalence of S. aureus ranged from 4% to 36% and count from 2 to 4 logCFU/g. The sed, sea, and seb genes in S. aureus isolates were detected with percentages of 40%, 26.6%, and 20%, respectively. The E. coli serotype O26 carried stx1, stx2, and eaeA. The APCs, Enterobacteriaceae counts, and Pseudomonas counts ranged from 5.1 to 7.2, from 2.01 to 3.9, and from 2.1 to 3.1 log CFU/g, respectively. The most probable number (MPN) of coliform ranged from 1.3 to 3.6 log/g. Levels of total volatile basic nitrogen and histamine ranged from 29.2 to 12.2 and from 0.6 to 4.6 mg/100 g, respectively. Also, the value of thiobarbituric acid was highly significant (1.1 ± 0.084 mg MDA/kg) in Trachurus mediterraneus samples compared with those levels obtained from other fish species. Our findings concluded that those fish species could constitute a public health hazard as fish are reservoirs for enterotoxigenic S. aureus and Shiga toxin producing E. coli strains. This study highlighted the importance of screening of fish for enterotoxigenic S. aureus strains and STEC isolates, and also assessing the quality parameters of fish.

Detection of harmful foodborne pathogens in food samples at the points of sale by MALDT-TOF MS in Egypt

“…Thus, rapid detection of pathogenic bacteria in foodstuffs ready for human consumption is of great importance to prevent foodborne disease outbreaks and ensure food safety [ 6 ]. In Egypt, the hazard of bacterial occurrence in the food chain exists [ 7 – 9 ]. Methicillin-resistant Staphylococcus aureus (MRSA) was isolated from humans, animals and milk samples [ 10 ] and implicated in several food poisoning outbreaks [ 9 , 11 ].…”

“…Methicillin-resistant Staphylococcus aureus (MRSA) was isolated from humans, animals and milk samples [ 10 ] and implicated in several food poisoning outbreaks [ 9 , 11 ]. Several foodborne illness outbreaks associated with consuming raw or insufficiently processed foods were reported [ 7 , 8 , 11 ]. The highly pathogenic E. coli O157 and other Enterobacteriaceae members were recovered with a high prevalence from dairy and meat products [ 12 ] and were responsible for severe illness among patients in different governorates [ 13 ].…”

The use of the so‐called ‘tubs’ for transporting and storing fresh fishery products

“…; however, survival of E. coli O157:H7 after 5 days at 10°C and 15 days at 27°C was reported in seawater (Miyagi et al, 2001;Williams et al, 2007) and detection after 30 days at 10°C was described in lake and river waters (Avery et al, 2008). Fishery and fishery products contamination may arise from faecal contamination of the farming or catching areas and pathogenic E. coli (mainly STEC, but also ETEC and EPEC) have been detected in fresh fish at landing or at market in Brazil, India, South Korea, Algeria and Egypt (Sanath Teophilo et al, 2002;Cardozo et al, 2012;Koo et al, 2012;Murugadas, 2016;Dib et al, 2018;Hussein et al, 2018) as well as in fish in aquaculture settings (Alagarsamy et al, 2010;Siddhnath et al, 2018), fishing ponds (Ribeiro et al, 2016) and fish droppings in aquaponic systems (Wang et al, 2020). Refrigeration temperatures are non-permissive for pathogenic E. coli, the minimum growth temperature being 7-8°C (ICMSF, 1996); however, outbreaks associated with fish or crustacean consumption are occasionally reported (EFSA BIOHAZ Panel, 2013, 2020.…”

Food Safety and Fish Production the Case of Staphylococcus aureus: A Review

“…Also, molecular methods based on the Polymerase Chain Reaction (PCR) in its different variants using the respective target genes encoding mainly enterotoxins (SE) (sea, seb, sec, sed, see and 16S rDNA) have been developed. These methods allow a greater number of samples to be analyzed, greater sensitivity, specificity and speed in obtaining results compared to traditional methods, they also allow epidemiological, evolutionary and phylogenetic studies (Manfredi et al, 2010;Saito et al, 2011;Jorda et al, 2012;Brizzio et al, 2013;Palomino-Camargo and González-Muñoz, 2014;Arfatahery et al, 2016;Wakabayashi et al, 2018;Hussein et al, 2019).…”