Early results are promising and programmes should be adopted more widely In a linked research paper (doi:10.1136/bmj.e4752), Braeckman and colleagues analyse the effectiveness of a monovalent rotavirus vaccine after its routine introduction in Belgium.1 This is the first study of its kind from Europe, and the new data offer robust evidence on the effectiveness of the vaccine in a real life setting. Public health problems are tackled by defining the extent of the problem, developing an intervention, and then deploying and evaluating the intervention. Each step is necessary for optimal control of the problem. Belgium is one of several countries that has recently implemented a nationwide rotavirus vaccination programme for controlling severe diarrhoea in children and it is currently evaluating the programme.1 Efforts to control rotavirus began in 1973, when Ruth Bishop identified wheel shaped (rota) virus-like particles in the intestinal mucosa of infants with diarrhoea.2 In the ensuing decades rotavirus was confirmed as the main cause of severe diarrhoea in children under 5 years, accounting for nearly 40% of hospital admissions and 450 000 deaths related to diarrhoea every year.3 Several decades of research resulted in the development of two new rotavirus vaccines (monovalent and pentavalent vaccines), which are now recommended by the World Health Organization …