10

A google for "Europe egg wash" will show up a lot of interesting results about differences in Egg processing and storage.

  • NPR says European chickens are vaccinated against Salmonella; and that US ones are not, but the egg washing has the same safety effect.
  • Forbes suggests that unless egg washing is done correctly, it is more likely to cause Salmonella infection than leaving unwashed. And thus implies that Eggs in Europe are safer because they don't run that risk.
  • The TV show good eats, as I recall, suggested the US egg washing was purely a matter of looks, and was partially responsible for Salmonella outbreaks.
  • io9 states: other countries don't need to refrigerate their eggs.
  • Salmonella is a living creature (rather than chemical caused by molecular breakdown etc), so presumably it can just simply be less concentrated in some areas.

I read a lot about egg related Salmonella in reference the the US. The wikipedia page only talks about Eggs in a US context, so it is kind of unhelpful for answering the question.

An excellent answer to this question would cite statistics talking about cases of egg related Salmonella in the US (per egg), vs similar statistics from other countries.

15

The short answer is "No," it's definitely not a US-only problem. Since the question makes comparisons between the US and Europe, I will focus mainly on those two areas.


Unfortunately, it's hard to estimate illnesses from eggs only, because frequently Salmonella outbreaks from eggs are due to how they are handled in the kitchen and what other foods they may contaminate.

If we just look at Salmonella cases overall, the most recent figures I could find from the EU (2014) list:

  • 88,715 reported (confirmed) cases, 23.4 cases per 100,000 population
  • 9,830 hospitalizations
  • 65 fatalities

The most recent figures I could find for the US (2013) list:

  • 7,307 reported (confirmed) cases, 15.2 per 100,000 population
  • 2,029 hospitalizations
  • 30 fatalities

(Note: these figures appear only based on a sample of the US population, so I'd pay attention to the incidence rate per 100,000 when comparing with the EU numbers.)

The problem, of course, is that in both the EU and the US the number of reported cases is only a small fraction of the total. A major study from the EU estimated that only 1 in 58 cases of salmonellosis is reported, which would suggest an annual incidence of perhaps 5 million cases. The CDC report from the US linked above estimates approximately 1.2 million cases every year.

Given that the population of the EU is around 500 million and the US is about 325 million, the incidence of Salmonella poisoning appears to be roughly double in the EU compared to the US, but again these are only estimates. (Also, it's notable that that last study says the incidence rate in various EU member states likely varies between about 16 per 100,000 and 11,800 per 100,000, which is obviously a huge range. Some countries are much more safe than others.)

Now, the question is: how many of these cases can be linked to eggs? Most studies suggest that eggs are the most common carrier of Salmonella leading to illness. From the above EU report:

Salmonella was rarely found in table eggs, at levels of 0.3% (single samples) or 1.0% (batch samples). The most important source of food-bourne Salmonella outbreaks was, however, still eggs and egg products.

In the US, one study from 2000 estimated somewhere around 180,000 illnesses annually from eggs, but another report estimated that the proportion of foodborne illnesses associated with eggs decreased from 6% in the late 1990s to 2% in 2006-2008. This was all before the new egg safety rule passed in 2010. (That link estimates 79,000 Salmonella cases annually associated with eggs before the rule.)

Compare that to the EU, which estimates 5.4 million cases of Salmonella in 2010, about 17% of which were likely attributable to eggs, or 928,000 cases in 2010. Given the differences in population, that suggests that Salmonella cases caused by eggs were about 7 times more prevalent in the EU compared to the US in 2010. That's the most recent year I could find decent figures for eggs alone to make a comparison. (Note that incidence various significantly across the EU member states. Those countries that have stricter policies, like the UK's vaccination policies, have much lower numbers.)

Estimates of the fraction of eggs in the US contaminated with Salmonella have often suggested a number around 1 in 20,000 (or 0.005%), based on a study from 2000. But that was before the new egg safety rule was introduced, and the numbers are likely somewhat lower now (given more frequent monitoring of infected flocks and their removal from production).


With all of that said, I sense in the question and the links provided a skepticism about US egg policy in general. Just to clarify a few points related to those sources:

  • Chickens are much more likely to be vaccinated in the EU compared to the US, but the percentage of infected chickens still varies significantly from country to country in the EU.

  • Improper egg washing is a problem, but guidelines for appropriate temperatures, etc. have become much more strict in the US over the years.

  • Egg washing is most definitely NOT just done for appearance. The US successfully lowered its Salmonella rates significantly earlier than many European countries through egg washing and refrigeration. Similar gains in safety have only recently been attained in Europe mostly through vaccination instead. The vast majority of Salmonella cases from unwashed eggs come from shell contamination. Without washing eggs, the only way to ensure safety is to make sure the exterior isn't contaminated in the first place (which means ensuring chickens aren't infected in the first place, e.g., through vaccination).

  • The last report I linked from the European Food Safety Authority states in its abstract: "An effective way to minimize any increase in risk during extended storage is to keep the eggs refrigerated both at retail and the household." The practice of not refrigerating eggs in the EU is likely a major contributor to the higher incidence of Salmonella cases mentioned above. In the US, refrigeration is required partly because of the washing process as well, which does increase shell porosity somewhat.

  • 1
    Many of your answers have struck me as very thorough, well written, and backed up with appropriate citations. This is no exception. +1 – Jolenealaska Mar 2 '16 at 0:39
4

In the UK there is the lion mark scheme. Each egg produced under this scheme is marked with a little lion. To qualify for this mark egg producers must follow a set of hygiene and storage procedures one of which is vaccination of all the chickens against Salmonella. No eggs sold by supermarkets in the UK are from non lion approved sources.

As far as I can tell there are no Salmonella cases traced back to lion marked eggs. The NHS no longer suggest pregnant women avoid soft cooked eggs.

If you buy eggs from a non-approved producer or keep your own hens then there is a possibility of Salmonella.

Generally I don't keep eggs in the fridge because they can absorb strong flavours and unless you want cheese or garlic flavoured eggs it's not great. However put an egg in a bag with a tiny bit of truffle and seal the bag in the fridge it's wonderful.

  • 1
    Wait, are you saying there's no salmonella cases at all from supermarket eggs in the UK? Citation? – Cascabel Mar 2 '16 at 1:16
  • 1
    @Jefromi Apparently yes, for a given value of “no cases”: the risk is low enough that raw eggs are now considered safe to consume for at-risk groups (e.g. pregnant women). See e.g. bbc.co.uk/news/health-41568998. – Konrad Rudolph Dec 13 '17 at 16:19
  • @KonradRudolph That's a good source, thanks! And... one that didn't exist yet when this answer and my comment weren't written :) Sounds like it demonstrates that this isn't an everywhere problem, but it's also not just US-only: this required a decades-long program that probably didn't happen in all non-US countries. – Cascabel Dec 13 '17 at 23:09

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