The listeria crisis in South Africa, which has claimed 180 lives thus far, has been described as the biggest documented outbreak the world has ever seen. 

Unlike other food-borne illnesses, listeria thrives in cold environments, making cold meat products such as polony, Russians and hams more susceptible to this bacteria since these foods are not usually cooked.   

Have a look at this timeline to find out more:  

Tauhira Dean & Jemima Lewin