Experts Use New Technology to Track US Listeria Outbreak
Experts at the ‘US Centers for Disease Control and Prevention’ (CDC), are using a technique called whole genome sequencing, to try to trace the listeria outbreak that has swept the country and caused three deaths in Kansas.
The technique, which maps all an organisms DNA, has only been used previously in medical research. It is now thought that the current outbreak, which has involved ice cream products manufactured by the company Blue Bell Creameries, could have its origins as far back as 2010.
The first indication of a problem came in January when random checks of a Blue Bell plant in South Carolina, found high levels of listeria contamination. As a result the company issued the first product recall in its 108 year history after the source of the contamination was traced to production lines in Brenham, Texas and Broken Arrow, Oklahoma.
Ten distinct listeria strains have been isolated from Blue Bell products, which are shipped to restaurants and supermarkets in 23 states from 62 distribution centre’s across America. On Monday, the company issued a total recall of all its products on the market after two samples of chocolate chip cookie dough ice cream tested positive for listeria.
Scientists from the US Food and Drugs Administration are still unsure of the origin of the contamination despite daily swab samples from the production line being sent for analysis. Blue Bell who have introduced a new testing programme hope to resume limited distribution soon.