How could you possibly know that

The Danish poultry farmers have been working extremely hard to eradicate salmonella. They do have some small insentive though. If you can prove that your countries chicks do not have salmonella, then the EU allows you to ban import chicks from countries that cannot make the same guarantees. This frees Danish poultry farmers from competing with German or eastern European farmers. The same laws applies to eggs, so throwing huge investments into figthing salmonella pays of in the long run.

Food safety in Denmark, and the rest of Scandinavia is a huge deal, but it's expensive.

http://sciencenordic.com/no-more-salmonella-danish-poultry

How it's actually ensured: http://www.oregonlive.com/health/index.ssf/2014/03/contamina...

> If you can prove that your countries chicks do not have salmonella, then the EU allows you to ban import chicks from countries that cannot make the same guarantees. This frees Danish poultry farmers from competing with German or eastern European farmers. The same laws applies to eggs, so throwing huge investments into figthing salmonella pays of in the long run.

That is a very clever, possibly even devious, way of fighting salmonella. Shield the ones who do it right from competitions by the ones who do it wrong. Maybe we should do that in more industries to get everybody to step up their game.

Your comment prompted me to ask DuckDuckGo that exact question, where I found a quite interesting report on the prevelance of salmonella in eggs: http://multimedia.food.gov.uk/multimedia/pdfs/fsis5004report...

Some take-aways:

The overall UK finding was that 9 samples (0.34%) were contaminated with Salmonella , which is equivalent to approximately 1 in every 290 “boxes” of 6 eggs.

Factors that might have influenced whether or not eggs were contaminated with Salmonella were also examined. However, where differences were found these tended to be small and much larger sample sizes would have been required to demonstrate a statistically significant difference.

There was no statistically significant difference between the prevalence of Salmonella contamination in samples purchased in England, Scotland, Wales or Northern Ireland; or between the prevalence of Salmonella contamination in samples from different egg production types; or between non-Lion code eggs and Lion code eggs; or between eggs that were stored chilled or at ambient temperature.

However, there was a statistically significant higher prevalence of Salmonella contamination of eggs from medium sized retailers* than large retail outlets.

*independent/local shops

He checks them. All of them.