Dr Pia Hardelid completed a PhD in infectious disease epidemiology in the Centre for Paediatric Epidemiology and Biostatistics at the UCL Institute of Child Health. She used data from a rubella serosurvey in newborn babies linked to birth records to determine maternal rubella susceptibility according to country of birth. Following her PhD, she worked as a statistician at the Health Protection Agency (HPA). During her time at the HPA she mainly worked on projects relating to influenza surveillance, including estimating influenza vaccine effectiveness, developing mortality monitoring systems, and analysing data from seroincidence studies of pandemic influenza A/H1N1.

Pia worked as a research associate in healthcare quality assessment at Imperial College before rejoining UCL to work with Professor Ruth Gilbert on a UK overview of childhood mortality in 2011.