The volume of international livestock trade increases every year, leading also to higher rates of disease. In the pig sector, the most recent examples of diseases rapidly spreading and affecting a number of countries are African swine fever (ASF), which is still prevalent in eastern Europe, or porcine epidemic diarrhoea virus (PEDv), which moved fast through Canada and large areas of the US.

In this context, biosecurity (the protection of agricultural animals from any type of infectious agent) becomes a key issue and has to be constantly reinforced to avoid the entrance of new diseases at country level and at farm level. This is called external biosecurity. However, diseases sometiems enter farms, as happened with Porcine Reproductive & Respiratory Syndrome (PRRS) in 2013, and there should be protocols in place to minimise the spread within farms. Biosecurity within the farm is called internal biosecurity. With the right biosecurity protocols, eradication of existing diseases is also possible.