Pathogenicity of Salmonella strains isolated from egg shells and the layer farm environment in Australia

Periodically? How about monthly. A table of egg-based Salmonella outbreaks is available at https://barfblog.com/wp-content/uploads/2014/12/raw-egg-related-outbreaks-australia-12-8-14.xlsx

aioli dressingIn Australia, the egg industry is periodically implicated during outbreaks of Salmonella food poisoning. Salmonella enterica serovar Typhimurium and other nontyphoidal Salmonella spp., in particular, are a major concern for Australian public health.

Several definitive types of Salmonella Typhimurium strains, but primarily Salmonella Typhimurium definitive type 9 (DT9), have been frequently reported during egg-related food poisoning outbreaks in Australia. The aim of the present study was to generate a pathogenicity profile of nontyphoidal Salmonella isolates obtained from Australian egg farms.

To achieve this, we assessed the capacity of Salmonella isolates to cause gastrointestinal disease using both in vitro and in vivo model systems. Data from in vitro experiments demonstrated that the invasion capacity of Salmonella serovars cultured to stationary phase (liquid phase) in LB medium was between 90- and 300-fold higher than bacterial suspensions in normal saline (cultured in solid phase). During the in vivo infection trial, clinical signs of infection and mortality were observed only for mice infected with either 103 or 105 CFU of S. Typhimurium DT9. No mortality was observed for mice infected with Salmonella serovars with medium or low invasive capacity in Caco-2 cells.

Pathogenicity gene profiles were also generated for all serovars included in this study. The majority of serovars tested were positive for selected virulence genes. No relationship between the presence or absence of virulence genes by PCR and either in vitro invasive capacity or in vivo pathogenicity was detected. Our data expand the knowledge of strain-to-strain variation in the pathogenicity of Australian egg industry-related Salmonella spp.

Food safety, Salmonella, sprouts and no, that dingo didn’t eat my baby

We used to be known as, “The no sprouts people.”

If Amy or I ordered anything, we’d say, no sprouts please.

sprouts.sorenne.jul.14We fell out of that habit because so much of foodservice in the U.S. has removed raw sprouts from the menu.

But it’s still 1978 in Australia.

With two weeks of school holidays, we decided on a mild road trip north to explore more of the country than the 15km radius we could reach by bicycle (yes, I know it’s not far, but is when hauling a kid in a trailer).

We spent three days at Rainbow Beach, including a day trip to Fraser Island, the world’s largest sand island. Our guide had been a chef for over 20 years and said, no more, gotta get back to what he loves, and that was hanging out on the Island.

We saw whales and four different dingoes going for bait from fishers; they didn’t eat any babies but we know a lot more about dingo safety.

Next stop: Hervey Bay, a renowned area for sea scallops and purportedly the best whale watching in Australia.

indulge.cafe.bundaburgWe arrived tired and went to a restaurant at lunch that had fabulous seafood, but raw sprouts on every dish.

We had forgotten we were the no-sprouts family, although I did have a word with the server on the way out.

Next, Bundaberg, sugar cane and rum capital of Australia, with a slavery past that has now somewhat transformed to a mixture of hippies and bogans.

Amy had looked on-line, and decided where we were going to lunch.

I placed the order, and the server explained all the food was local and naturally sourced. I internally groaned and rolled my eyes.

Then I remembered I needed some tomato sauce —  what North Americans would call ketchup – for the kid.

dingo.beach“Oh, you don’t want the aioli?”

“No, wait, can you tell me how the aioli is made? Does it contain raw eggs?”

Oh yeah, everything here is made from scratch, but I’ll check.”

Thirty seconds later, the chef appeared.

“We only use commercial mayonnaise for mayo and aioli. Everything else we make from scratch but not this one.”

Why?

Because my brother was one of the 220 that got sick from Salmonella from raw-egg mayo on Melbourne Cup day in Brisbane in 2013. And I’m not putting my business at risk over one decision that is easy to make.

Good on ya.

A table of raw egg related outbreaks in Australia is available at https://barfblog.com/wp-content/uploads/2014/03/raw-egg-related-outbreaks-australia-3-3-14.xlsx.