There have been numerous controversies regarding vaccines in the past. The recent scare regarding the safety of cervical cancer vaccine is a small reminder of the trials it had to face in the court of public judgement.
The authors explore two such vaccine controversies to identify missed opportunities and lessons that could be learnt.
a) The diphtheria-pertusis-tetanus vaccine was routinely used in public health with an established safety record. In 1974, a case series from Hospital for Sick Children at Great Ormond street, described 36 children who suffered severe neurological complications following their DTP immunisation.
The negative publicity resulted in a sharp decline in vaccine uptake from 77% to 33%.There was uncertainty among the public and practitioners with regards to its safety until the National Childhood Encephalopathy Study was published 7 years later.
b) The measles-mumps-rubella (MMR) vaccine was introduced in the U.K in 1988.It suffered a major setback following the study by Wakefield et al in 1998 suggesting an association between MMR and autism. There were several publications in the press in the following years, which conveyed ambiguous messages with no clear scientific consensus on MMR safety. MMR vaccine uptake dropped to 84% resulting in a mumps epidemic in 2005. Currently, measles is declared to be endemic in the U.K.
The delay in robust defence of MMR vaccine until the Cochrane review in 2005, contributed to undermining confidence in MMR safety.
Conclusion Significant delay has occurred in the past in responding to such public health controversies, resulting in increased morbidity and mortality. In the future, strategies have to be developed within the department of health, through existing agencies like the National Institute for Health and Clinical Excellence, to promote early response and prompt development of scientific consensus to guide health professionals and public in adopting evidence-based practice.