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العنوان
Staphylococcal food poisoning sources and Strategy for control in Human /
المؤلف
Attia, Tarek Abd EL Tawab.
هيئة الاعداد
باحث / طارق عبد التواب عطيه
مشرف / مها أحمد صبرى
مشرف / خالد عبد العزيز عبد المعين
مشرف / داليا أنور حمزة
الموضوع
Enterotoxins.
تاريخ النشر
2018.
عدد الصفحات
107 p. :
اللغة
الإنجليزية
الدرجة
ماجستير
التخصص
البيطري
تاريخ الإجازة
1/1/2018
مكان الإجازة
جامعة القاهرة - كلية الطب البيطري - Zoonoses
الفهرس
Only 14 pages are availabe for public view

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Abstract

Food-borne diseases are of major concern worldwide, Staphylococcus aureus among the predominant bacteria involved in these diseases; it is a leading cause of gastroenteritis resulting from the consumption of contaminated food. Therefore a total of 483 food samples (246 chicken & 237 beef meat) and 120 equipment swab samples that retailed at 112 food outlets in Egypt were investigated bacteriologically for contamination with S. aureus. Additionally, 121 hand swabs of food handlers were gathered from the same outlets. S. aureus was isolated from 57 (11.8%), 4 (3.3%) and 13 (10.7%) food, equipment and hand swabs samples, respectively. The higher rate of isolation of S. aureus was observed in chicken meat (13.8 %) than those recorded in the examined beef meat (9.7%). Using PCR, 18 (29.5%) of 61 isolates were enterotoxigenic, in addition only 2 (15.4%) of 13 isolates belonged to the human were enterotoxigenic. Most of the enterotoxigenic isolates belonged to raw chicken samples (37.5%) followed by the cooked beef meat (30.0%). At least one of the following enterotoxins coding genes was detected in 20 enterotoxigenic strains SEC, SED, SEG, SEH; some isolates were found have more than one SEs genes and none of those carries SEA, SEB or SEE. Among the SED-producing isolates (chicken, beef, knife and human swab samples) sequencing and phylogenetic analysis evidenced that both cooked chicken and beef meats as well as knife sequence were grouped in the same cluster with the human sequence rather than raw chicken which placed in another one. Such phylogenetic analysis may point out to the incrimination of food handlers in the contamination of not only cooked food but also articles such as knife mentioning that this isolate obtained from a knife used only for cutting cooked food. Therefore, there is an urgent demand to establish a food safety program that prevents, eliminates, or reduces the risk of food contamination at each point in the flow of food. So ISO 22000:2005 with ISO/TS 22002-2:2013 Standards was applied for 45 days on 56 food outlets evidenced contamination with S. aureus. The microbiological examination within the investigated food outlets evidenced no S. aureus yielded after implementation of ISO 22000:2005 which prove the efficiency of this system.
The study concluded that chicken and beef meat act as potential vehicle for transmission of S. aureus and the consumers are at risk of staphylococcal food poisoning if strict hygienic and preventive measures to void Staphylococcal enterotoxins are not considered.