It has recently been estimated that the global burden of diarrhoeal disease in children < 5 years of age is ∼1.7 billion new infections with 0.7 million deaths per year (Walker et al., 2013). These figures make diarrhoeal diseases, after respiratory tract infections, the second most common cause of mortality in young children in low-income countries (Liu et al., 2012; WHO, 2014). Further contemporary data from the Global Enteric Multicentre Study, the largest prospective case–control study on paediatric diarrhoeal illnesses in sub-Saharan Africa and South Asia ever conducted, identified Shigella to be amongst the most common diarrhoeal pathogens in these high-incidence settings (Kotloff et al., 2012, 2013).