In 2014, WHO estimated that approximately 4ยท2 million severe complications leading to hospital admission and 4200 related deaths occur globally each year because of varicella (also known as chickenpox).1 By comparison with other vaccine-preventable diseases in childhood, such as measles and diphtheria, mortality and morbidity from varicella are lower.2 However, the frequency of infection and indirect costs such as from parents taking time off from work, mean varicella has a substantial, albeit underestimated, economic impact.