An outbreak of smallpox in Bradford in 1962 first came to attention on 11 January 1962, when a cook from the children's hospital in Bradford, West Riding of Yorkshire, England, presented with an unexplained fever and was found to have changes in her blood similar to another sick person at the nearby St Luke's Hospital, both samples appearing compatible with smallpox.

The index case was later discovered to be a nine-year old girl who arrived in the UK on 16 December 1961 from Karachi, Pakistan, where there was an ongoing epidemic of smallpox.

Between December 1961 and April 1962, authorities became aware of an ongoing epidemic of smallpox in Karachi, where people were able to depart via charter flight and arrive in the UK, where surveillance at airports was enhanced only following the first imported case.

In Roberta Bivins' account of the epidemic published in 2015, she described Bradford as having "prided itself on a reputation for tolerance and good intercommunal relations".

[4] In all, of the five people with smallpox that had arrived at Heathrow from Pakistan, two travelled to Birmingham, one to Cardiff, one to Bradford and one stayed in London.

The other was Jack Crossley, a 40-year-old abattoir worker who had been admitted to Tovey's own hospital, St Luke's, and who died shortly after the blood was taken.

After examining the man in the mortuary and without waiting for laboratory confirmation, the diagnosis was assumed and the regional medical officer convened a committee.

[4][11] Her international vaccination certificates were up-to-date and when she was admitted to A1 ward at Bradford's Children's Hospital, her diagnosis and treatment of malaria masked any suspicion of smallpox.

[11][15] On 12 January 1962, the Telegraph & Argus, Bradford's local daily newspaper, reported "Smallpox Fear: 2 Die".

Bivins' described that the Argus was "careful not to exaggerate the role of immigration", noted the paper to frequently quote medical authorities, acknowledged that it reported that Pakistani residents were just as vulnerable and that Pakistan itself had been implementing its own vaccination measures.