This qualitative study examines how parents have conceptualised the MMR controversy and offers an assessment of parents’ perceptions of vaccine-preventable diseases and childhood immunisation. Methods-Eighteen focus groups were conducted in central Scotland between November 2002 and March 2003, with a diverse range of parents to ensure maximum variation in terms of age, socio-economic circumstances, likely views about vaccination and family circumstances. Findings-There are some potentially serious misunderstandings and gaps in knowledge about many of the diseases, which generally led to a diminished sense of urgency for vaccination. Parents deciding about MMR vaccination have to balance the perceived risk of disease against the perceived risk of MMR, and the perceived ability of their child’s immune systems to cope with the challenge of vaccines, or to fight the disease. Parents often questioned the safety of combining several antigens into one vaccine, as they were concerned it could be too potent for their child’s immune system and could potentially cause long-term damage. In some circumstances parents preferred to withhold MMR vaccination because it was easier for them to live with the risk of their child naturally contracting one of the diseases than with the risk of causing their child permanent damage as they perceived other parents may have unwittingly done. There is also a need for further research to investigate how parents caring for autistic children have been affected by the debate and to reassure parents based on sound evidence that giving these vaccines in a combined form is safe. Indeed, as the new pentavalent vaccine (DtaP/IPV/Hib) is introduced into the programme, it is crucial that these concerns about immune overload are taken into account to reassure parents in their wider reappraisal of vaccine risk.

En France, la vaccination repose principalement sur l’action des médecins généralistes (MG). L’augmentation de l’opinion défavorable du public envers la vaccination, associée au constat d’une couverture vaccinale insuffisante, démontre l’importance de prendre en compte les attitudes et perceptions des MG vis-à-vis de la vaccination. Les objectifs de ce travail de thèse étaient d’évaluer les connaissances, perceptions, attitudes, et pratiques des MG français vis-à-vis de certains vaccins, pour lesquels la couverture vaccinale est sub-optimale et/ou pour lesquelles des polémiques existent. En 2014, une vague d’enquêtes par questionnaire téléphonique a été mise en place auprès de 1582 MG français pour mieux connaître leurs comportements, attitudes et pratiques vaccinales. Plusieurs résultats ont mis en évidence l’hétérogénéité des pratiques et des perceptions des MG concernant la vaccination. Tout d’abord, nous avons mis en évidence que les MG avaient une attitude discordante entre leurs pratiques vaccinales pour leurs propres enfants et leurs recommandations vaccinales pour leurs patients. Ensuite, nous avons étudié la perception par les MG des polémiques vaccinales concernant les effets indésirables des vaccins. Cependant, les MG interrogés étaient soit sensibles aux polémiques, soit les rejetaient, sans que cela soit associé au caractère fondé ou non de la polémique. Puis nous avons étudié les recommandations des MG pour la vaccination à méningocoque C, qui étaient très insuffisantes dans notre étude, ce qui participe à la couverture vaccinale basse de ce vaccin. Le manque de communication autour de ce vaccin pourrait être imputé en partie à une campagne de vaccination insuffisante. Par la suite, nous avons étudié la décision des MG face à un enfant devant être vacciné, mais présentant une infection mineure fébrile. Une majorité des MG a préféré reporter cette vaccination, la fièvre étant le facteur influençant le plus cette décision. Les recommandations officielles françaises ne permettent pas de définir clairement l’attitude à adopter dans cette situation. Enfin, nous avons décrit les outils plébiscités par les MG pour améliorer leur pratique vaccinale au quotidien. Certains de ces outils existent mais semblent manquer de visibilité. En conclusion, les MG ne peuvent améliorer leurs pratiques qu’avec une formation spécifique à la vaccination, des outils identifiés et disponibles, et un soutien des pouvoirs publics qui s’engagent avec des recommandations claires / In France, vaccination relies mainly on general practitioners (GPs). The increase in the public's unfavourable opinion on vaccination, associated with the insufficient vaccination coverage, demonstrates the importance of taking into account the attitudes and perceptions of GPs regarding vaccination. The objectives were to assess the knowledge, perceptions, attitudes, and practices of French GPs regarding vaccines with insufficient vaccination coverage and / or for which controversies exist. In 2014, a telephone survey questionnaire was conducted on 1582 French GPs to learn more about their behaviours, attitudes and vaccine practices. Our results have highlighted the heterogeneity of GPs’ practices and perceptions regarding vaccination. First, we found that GPs reported discordances between their vaccine practices for their own children and their vaccine recommendations for their patients. Then, we studied the GPs’ perception of the vaccine polemics concerning adverse effects of some vaccines. However, the interviewed GPs were either sensitive to the polemics or rejected them, without being associated with the well-founded nature of the controversy. Then we looked at GPs’ recommendations for meningococcal C vaccination to their patients, which were very low in our study. These low recommendations contributes to the low vaccine coverage of this vaccine. The lack of communication about this vaccine could be partly attributed to an insufficient vaccination campaign. Subsequently, we examined GPs’ decision facing a child to be vaccinated, but presenting an uncomplicated common cold. A majority of GPs decided to postpone this vaccination, with fever being the most important factor influencing this decision. The French official recommendations do not define clearly the attitude to be adopted in this situation. Finally, we described the tools that GPs would find useful to improve their daily immunization practice. Some of these tools exist but seem to lack visibility. In conclusion, GPs can only improve their practices with specific immunization training, identified and available tools, and with the support of public authorities who commit themselves with clear recommendations