14 DAY TRIAL // A team of investigators at the University College Cork is finally shedding some more light on the reasons why bacterial infections that cause food poisoning are so unpredictable.
The team says that the microorganisms have over millions of years of evolution adapted to a lifestyle that follows a single goal – boosting their chances of survival.
In order to accomplish this objective, they employ a variety of means, or combination thereof, which is one of the main reasons why researchers have such a difficult time predicting outbreaks, or even single food poisoning cases.
Additionally, poisoning only happens some of the times when we are infected with harmful bacteria, whereas other times our immune systems manage to defuse the situation before it gets serious.
Other time, all it takes to stop food poisoning is the acidic environment of the gut and stomach, which kills numerous bacterial species that would otherwise cause problems.
But sometimes even these defense mechanisms are not enough, and infections occur. In the work the experts present, they shed light on how the bacteria Listeria moves past the body's security systems.
The work is presented by team leader Colin Hill, at the autumn meeting of the Society for General Microbiology, which is being held in Nottingham, England.
Listeria is a common occurrence in chilled products and in soft cheeses, and it is apparently capable of defeating the acidic conditions of the stomach, ScienceDaily reports.
It does so by employing the unwilling help of key food ingredients. This cannot be allowed to happen because Listeris is oftentimes fatal if left unchecked, and affects pregnant women and seniors especially hard.
The bacteria make use of amino-acids and glutamate, two substances commonly found in foods, in order to neutralize the acid that would otherwise destroy them. This allows them to escape the stomach unscathed.
“People who consume foods that are contaminated with Listeria and are also high in glutamate, such as soft cheese or meat products, have a higher chance of developing serious infection than someone eating the same quantity of bacteria in a low-glutamate food,” Hill explains.
“Of course this is further complicated by the fact that a contaminated, low-glutamate food could be eaten in combination with a high-glutamate food such as tomato juice, which could also increase the risk of infection,” he says further.
“The number of cases of listeriosis has nearly doubled in the last decade in Europe. This is because the bacterium is so good at overcoming the challenges it faces in food and in the body,” he concludes.