Due to low uptake of the MMR vaccine across the world, we have seen a dramatic rise in the number of cases of measles and mumps. These have gone against efforts to eradicate these diseases. Perceived safety concerns have led to the rise in uptake of single vaccines and thus for a number of years the UK has not had nor licensed a single mumps vaccine thus leaving a considerable proportion of people unvaccinated. A private clinic now wants to sell an EU-produced single vaccine in the UK. This vaccine has not passed adequate safety tests. But is it really any worse than what we have?