An investigation into an outbreak of Salmonella enteritidis phagetype 4 infection and the consumption of custard slices and trifles

Abstract

Epidemiological investigation into an outbreak of food poisoning in 17 patients caused by Salmonella enteritidis phage-type 4 demonstrated a highly significant association with consumption of custard, retailed in custard slices and trifles from a bakery on one day. The bakery had changed their recipe for custard 2 weeks earlier to include fresh shell eggs and had not followed earlier national advice on cooking eggs for human consumption. The case-control study supports earlier work associating Salmonella enteritidis phage-type 4 infection with consumption of uncooked or lightly cooked shell eggs.

Consecutive salmonella outbreaks traced to the same bakery

“…The vehicle of infection in the first outbreak was custard slices from a single day's production at the bakery sold at a number of independent retail outlets. Unlike a previously described outbreak involving custard slices, the custard was made from a reconstituted custard powder mix and did not contain eggs [5]. A sample of residual custard powder mix was negative for salmonellae.…”

Microbiological quality of Portuguese custard tarts in Toronto—a pilot study

“…There are very few studies that have investigated this specific type of product, but other studies on similar custard-based baked goods have suggested custard can support microbial growth and lead to illness if contaminated (Barnes and Edwards, 1992;Evans et al, 1996). Proper temperature controls are a vital preventative measure against the growth of pathogenic organisms, and by storing food at 4°C or less most bacterial species will have limited growth (Ontario Agency for Health Protection and Promotion, 2013).…”

“…The custard slices responsible for the outbreak had been cross-contaminated during the preparation stage of the cold-custard mix, and once the custard slices had been made they were not refrigerated (Evans et al, 1996). Similarly, another bakery selling custard slices caused multiple cases of food poisoning in the United Kingdom in 1991 (Barnes and Edwards, 1992). The bakery had changed its recipe to include fresh shell eggs and was not fully cooking them before sale, resulting in the contamination of the custard slices with Salmonella Enteritidis (Barnes and Edwards, 1992).…”

“…Similarly, another bakery selling custard slices caused multiple cases of food poisoning in the United Kingdom in 1991 (Barnes and Edwards, 1992). The bakery had changed its recipe to include fresh shell eggs and was not fully cooking them before sale, resulting in the contamination of the custard slices with Salmonella Enteritidis (Barnes and Edwards, 1992). Prior to their sale, the custard slices had been held at ambient temperature during storage and transportation, and they were then left at 10°C for display in the shop (Barnes and Edwards, 1992).…”

“…The bakery had changed its recipe to include fresh shell eggs and was not fully cooking them before sale, resulting in the contamination of the custard slices with Salmonella Enteritidis (Barnes and Edwards, 1992). Prior to their sale, the custard slices had been held at ambient temperature during storage and transportation, and they were then left at 10°C for display in the shop (Barnes and Edwards, 1992). The improper cooking and the lack of temperature controls leading up to the sale left the Salmonella in a perfect medium for growth.…”