Infection outbreaks linked to ready-to-eat salads
Who has never bought a bag or tray of ready-to-eat salad at a supermarket ?
Lately these time-saving food products have had a big boom due to healthy eating campaigns, but they have also been blamed as the cause of certain infection outbreaks, from salmonella, listeria to e-coli in the US and in Germany and now cryptosporidium in the UK.
Anything that is grown directly in soil can be linked to food-related illnesses, because some pathogens can only be killed by heat, strong detergents or irridation, and simply not by just washing them with water like we do at home, while ready-to-eat salads are washed in water with sanitizers such as chlorine compounds, then rinsed thoroughly and spun dry – all at cold temperatures.
Last May, three hundred people were reported to have contracted cryptosporidium between England and Scotland.
Cryptosporidium is caused by parasite that causes the disease cryptosporidiosis, which causes an acute, short-term infection with the most common symptom being diarrhea, and potential sources of contamination can come not only from food, but also from water, swimming or even poor personal hygiene.
The Health Protection Agency investigated the outbreak and claimed said there was "strong evidence" of an association between those who fell ill with ready-to-eat salads, however the Food Standards Agency, which was part of the outbreak control team led by the HPA, could not identify the source of the contamination.
The agency found that a 25% sample of those who fell ill, 46% indicated that they had consumed the same mixed-salad product, that was associated with being bought at Morrisons or Asda supermarket chains.
Dr. Stephen Morton, who lead the HPA investigation said, “Our findings suggest that eating mixed-leaf bagged salad was the most likely cause of illness." However he did add , “It is often difficult to identify the source of short-lived outbreaks of this type as by the time that the outbreak can be investigated, the affected food and much of the microbiological evidence may no longer be available” and “that different retailers often share the same suppliers and that other retailers could also have been affected.”
Naturally both supermarket chains were not happy with the results and disputed the findings claiming that they have not had any complaints and that they use the same supply chain as several other retailers, meaning they too would also have been affected by this outbreak. Another said that HPA’s research is ‘statistically flawed’.
So how do you avoid food contamination? The FSA's director of food safety, Dr Alison Gleadle gave consumers this basic tip: "We'd like to remind everyone of our usual advice to wash all fruits and vegetables, including salad, before you eat them, unless they are labeled ready to eat. It's also important to wash hands thoroughly as well as clean chopping boards, knives and other utensils between preparing raw and ready-to-eat foods to prevent cross-contamination."