Cork doctor had crucial role in combating smallpox

John Milner Barry, a Cork medical practitioner, was an early vaccination convert in Ireland after he recognised in 1800 that variolation was not effective enough to eradicate smallpox, writes Laurence Geary of UCC's History Department

Edward Jenner vaccinating patients in the Smallpox and Inoculation Hospital at St Pancras in London. Jenner had noticed that farm workers who contracted a mild pox disease from livestock, usually from milking infected cows, were subsequently immune to natural and inoculated smallpox. Watercolour after J Gillray, 1802: Wellcome Collection

Smallpox or variola is the only human disease to have been eradicated by vaccination, the last natural case occurring in 1977. 

For centuries, this acute highly infectious viral disease was feared and loathed in Ireland and elsewhere because of its disfiguring effects and relatively high mortality rate, often around 20%. Except in the rarest instances, there were only two ways in which smallpox infection could end – in death or with long-term protection against recurrence.