Interregional foodborne salmonellosis outbreak due to powdered infant formula contaminated with lactose-fermenting Salmonella virchow

Abstract

Spain's Salmonella surveillance system backed by regionally-based epidemiologists around the country made it possible to detect and halt the spread of a foodborne salmonellosis outbreak due to powdered infant formula contaminated with a lactose-fermenting strain of Salmonella virchow. Forty-eight cases involving children, mostly under 7 months old, were detected in 14 out of Spain's 17 Regions. The outbreak started in January and ended in June 1994. All cases were microbiologically confirmed. The implicated strain had a 3.6 kb plasmid, was susceptible to all antimicrobials tested except nitrofurantoin and was phagetype 4a. Isolates from 8 of 24 Brand "A" milk samples tested had the same characteristics as case isolates. All affected/suspect batches of Brand "A" milk were destroyed and the product withdrawn from sale, which led to the end of the outbreak. This incident underscores the importance of maintaining surveillance systems able to detect and prevent foodborne outbreaks and alert to the possibility of isolating unusual lactose-fermenting Salmonella serotypes in especially sensitive food products.

Two Consecutive Large Outbreaks of Salmonella enterica Serotype Agona Infections in Infants Linked to the Consumption of Powdered Infant Formula

“…Nevertheless, this low-grade contamination was responsible for a large outbreak of 136 confirmed cases and probably more nonconfirmed cases. In previous outbreaks of Salmonella infections linked to powdered milk [11][12][13][14][15] or to other food products, 6,7,10,16,17 similar low concentrations of Salmonella were reported suggesting a low infectious dose. A review of 11 outbreaks of salmonellosis for which the infective doses could be calculated revealed that in 6 outbreaks, calculated ingested doses were less than 10 3 organisms.…”

Risk Factors for Salmonella Gastroenteritis in Children Less Than Five Years of Age in Taiwan

“…22 Contamination of dry milk products with Salmonella has been previously recognized and linked to several outbreaks affecting hundreds of infants. [23][24][25] It was possible that the contamination occurred in only some products made by certain manufacturers. Unfortunately, the information regarding the brands or manufacturers of the powdered milk was not collected.…”

InvasiveEnterobacter sakazakiiDisease in Infants

“…Powdered infant formula also has been associated with outbreaks of illness due to Citrobacter and multiple Salmonella serotypes (13,(34)(35)(36)(37)(38). The degree to which E. sakazakii is a marker for a range of neonatal infections possibly related to powdered infant formula remains to be defined.…”