This book is a significant addition to the history of medicine and health in twentieth-century Ireland. It charts the origins of childhood immunization in Ireland. It identifies the diverse factors which supported or obstructed the introduction of active immunization, and examines the rationale underpinning them. It highlights the centrality of municipal medical officers of health: their role in incepting and supervising local preventive public health initiatives in the face of popular resistance, and the uncooperative, and at times obstructionist stance adopted by the wider medical community.

In the 1920s, active immunization was a radical new public health intervention, widely considered to be in its experimental stage. It was rejected by government and by the medical community in Britain on that basis. The question then is why health authorities in the Irish Free State felt compelled to embark on such a largely untried intervention?

The study demonstrates that despite the distinct absence of diphtheria from the statistical record, the disease was rampant, and at times the most fatal of all childhood diseases in Ireland. Medical and popular ignorance as to the cause, nature, and treatment of diphtheria, combined with issues relating to nomenclature, and the reluctance of local authorities to have what was perceived as a new public health threat listed on their health reports, conspired to effectively obscure the true prevalence of diphtheria in Ireland. Such obfuscation simply allowed diphtheria to thrive and propagate, cloaked by doctors and local authorities unable or unwilling to intervene. Furthermore, diphtheria failed to feature prominently in the statistical record because there was no compulsion on local authorities to submit district reports of infectious diseases. Where national statistics are available, they are compiled from reports returned on a voluntary basis and at the discretion of local health authorities. This suggests that historians of health must approach the statistical data with some caution as the method of disease notification in nineteenth-century Ireland produced what can only be regarded as a partial and largely unreliable record.

Interpreting the statistical record is again confounded since the incidence of diphtheria in the Free State appears to increase substantially immediately following the introduction of anti-diphtheria immunization.