Ready to eat salad is considered one of the products most likely to cause food-related illness, said Professor Hugh Pennington, an emeritus professor of bacteriology at the University of Aberdeen in Scotland -- who worked for the British, Scottish and Welsh governments as an expert on microbiology and food safety. His claim follows a Health Protection Agency investigation into an outbreak of salad-linked Cryptosporidium infections that affected around 300 people in England and Scotland in May.
In the analysis of the exposure to different salad vegetables a significant statistical association was found between infection and the consumption of pre-cut spinach. The strongest association with infection was found to be with consumption of ready to eat pre-cut mixed salad leaves from a major supermarket chain. These findings suggest that one or more types of salad vegetables could have been contaminated. So reminder to everybody that wash your ingredient thoroughly and avoid pre-packed meals so it's better to have a list of good salad recipes.
That is largely because greens are grown directly in the soil, and some pathogens can only be killed by heat or strong detergents, not just water. Certain types of bacteria found in the ready to eat salad bags can be almost impossible to kill, unless the leaves are irradiated - a process the public would oppose.
"You could irradiate it - but that would be a `no, no` with the public. You just can`t be absolutely sure that the bagged salad you are buying - which has been put through a chemical wash to kill the bugs, is actually free of them." Food pathogens are very good at clinging on to salad and the risk from cryptosporidium, salmonella and listeria is very real. "I would advise people to thoroughly wash salad even when it says it has been washed and is ready to eat," Pennington said.
Vegetables are fine and safe if they are cooked in the traditional way of boiling them to death. The only danger comes when you eat them raw.
The responsibility falls on the people who produce food. But much of our vegetables are now grown in countries that do not necessarily have the same hygiene standards. The consumer has no way of knowing how the food has been produced.
Cryptosporidiosis is most common in children aged between 1 and 5 years, but it can affect anyone. People with weak immune systems are likely to be most seriously affected.
There is no specific treatment for cryptosporidiosis. Most people with a healthy immune system will recover within one month. It is important to drink plenty of fluids to avoid dehydration.
Cryptosporidium is found in soil, food, water, or surfaces that have been contaminated with infected human or animal faeces. People may also be infected by consuming contaminated water or food.