Focus on Salmonella

Many people will be familiar with Salmonella from the risk to food safety associated with eating eggs drawn to the attention of the public by the then Health minister Edwina Curry in the 1980’s

Salmonella causes a food borne bacterial infection normally associated with gastroenteritis, diarrhoea and vomiting.

However, some types of salmonella are also associated with more severe infections such as bacteramia and Typhoid fever.

The increase in incidence of Salmonella in the 1980s was associated with one type of Salmonella called Salmonella Enteritidis that was in table eggs

It took nearly two decades to tackle the Salmonella Enteritidis problem, by the introduction of a vaccine in layer flocks and improved biosecurity at farms

The Salmonella in eggs epidemic was associated with a rise in the number of cases of human Salmonellosis from around 10,000 per year to around 30,000 per year in England and Wales

Today we have returned to pre-epidemic levels of Salmonella disease, but Salmonella remains a significant cause of morbidity and mortality

While much of the media spotlight of food-safety has now fallen on Campylobacter, the greater severity of Salmonella infections means that it may have a disproportionate impact on the economy as it is more likely to lead to hospitalisation or even death

With the epidemic of Salmonella in hen eggs now largely controlled, there is great interest in decreasing the incidence of salmonella in other food livestock – In particular pig breeding.

At the Institute of Food Research in Norwich, we are using modern molecular and whole genome sequencing methods to tackle the current food safety issues

We are using the genetic signatures, or bar codes of the bacteria, identified by whole genome sequencing, to track the pathogen in livestock and food supplies around the world

This is allowing us to understand the risk factors associated with the bacterium gaining access to the food supply

We are also reading the genetic material within the bacterium to identify how the bacterium survives persist in livestock, enters and survives in food and causes disease in people

The genetic book that is the whole genome sequence of Salmonella holds the key to designing new ways of keeping consumers safe from this disease