Improving foodborne disease surveillance on a global scale

Foodborne disease surveillance is not easy because of the difficulties of linking cases of disease with the contaminated food source. Roughly 10% of people fall ill each year after eating contaminated food but identifying the source of the contamination is not simple, especially as symptoms sometimes only become evident weeks after the pathogen-containing food was consumed. With food now a global commodity, identifying sources of foodborne disease must be looked at and communicated globally rather than on a country or regional scale.

PulseNet International, a global network of public health laboratory networks, dedicated to bacterial foodborne disease surveillance, is advocating the use of whole genome sequencing (WGS) to improve detection of and response to foodborne illnesses and outbreaks.

Multilocus sequence typing exploits the unambiguous nature and electronic portability of nucleotide sequence data for the characterisation of microorganisms. As sequence data are truly portable between laboratories, one expanding global database per species can be maintained on the World Wide Web enabling exchange of molecular typing data for global epidemiology via the internet.

The sharing of information within regional and global public health laboratory networks will increase efficiency and enable data to be compared across countries in real time, which is currently not the case. This is especially important due to international travel and trade. Linking human cases with contaminated food sources on a global level will ultimately save lives and money.

According to PulseNet International’s article in the June issue of Eurosurveillance, common steps for validation studies, development of standardised protocols, quality assurance programs and nomenclature have been agreed. The article also asserts that a global standard method for primary sequence data analysis based on whole genome Multiple Locus Sequence Typing (wgMLST) and derived public nomenclature will be adopted.