▽ScienceDirect - Vaccine ●12/31 15:37 Ivan Hung, MBChB MD FRCP (Lon, Edin)The University of Hong Kong, Department of Medicine, Hong Kong SAR, ChinaAngela Rasmussen, PhDVaccine and Infectious Disease Organization International Vaccine Centre, Saskatoon, CanadaFlorian Krammer, PhDIcahn School of Medicine at Mount Sinai, New York, United States of AmericaResearch articleOpen accessWhat makes an expert in childhood vaccinations? Pe