When William Weipers was appointed director of the Glasgow veterinary school on its absorption into Glasgow University in 1949 he recruited a team of bright young graduates who earned Glasgow a unique place in the scientific spectrum. One of this group was William Fleming Jarrett. Jarrett, universally known as Bill, went on to establish an international reputation for his work on the viruses causing cancer – work that led to major developments in the treatment of the disease in animals and humans. He was instrumental in developing the research that identified the viruses causing leukaemia and Aids.
This work had its roots in a clinical investigation. A number of cats in a Glasgow household all developed a type of cancer: lymphoma. Jarrett was asked to investigate. He reckoned the disease must be contagious, although cancers had not previously been thought to be transmissible in this way. Eventually he discovered a virus was responsible, the feline leukaemia virus.
Jarrett and his colleagues refined techniques for identifying the virus and to develop a vaccine against it, with the result that the feline leukaemia has been virtually eliminated. Collaboration with scientists from the US International Cancer Institute led to studies of human viral cancer and the identification of the human immunodeficiency virus, the cause of Aids.
By 1964, when the feline investigation began, Jarrett's career was in full swing. In 1952, he was one of a group which developed a vaccine against a disease of cattle, parasitic bronchitis ("husk"). Widespread, particularly in Western Scotland, husk was the cause of major economic loss.
The disease was caused by a helminth, the lungworm. By a combination of microbiological and immunological techniques it proved possible to modify the lungworm larvae by irradiation so that it produced immunity to infection by the natural strain without itself causing the disease. The vaccine, produced commercially as Dictol, is still in use.
A later development was a study of cancers in cattle which was behind the production of a vaccine against the viruses that cause cervical cancer in women. A high incidence of stomach cancers in Highland cattle was found to be due to a papillomavirus. The virus itself, however, produced only a benign form of tumour. It was only when the animals grazed bracken that the virus became virulent: Jarrett found that the plant contained a factor that triggered malignancy. A bovine papilloma vaccine was developed that was the model for the human product.
Jarrett's interest in the possible application of the results from studying animal diseases to similar conditions in humans began early: as part of his PhD studies he spent time studying human pathology at Glasgow Western Infirmary.
Appointed a lecturer in 1952, he was soon promoted to Reader in Pathology, He spent his entire career at Glasgow, apart from a secondment to Kenya in1963 as part of a group charged with setting up a veterinary school in Nairobi. While there, he found time to study the bacterium responsible for causing East Coast fever (theileriosis), a cattle disease with serious consequences for the cattle-based economy of the area.
While in his thirties, Jarrett was appointed to a personal professorship in 1965, then in 1968 to a university chair as Professor of Pathology.
His talents were by not confined to research; he was regarded as an inspirational teacher and popular co-worker. One of his student contemporaries (and later colleague), now Sir James Armour, said, "He never seemed to do much work but always came top in exams". In his younger days he was an accomplished jazz trumpeter, guesting with a popular local band, the Clyde Valley Stompers.
William Fleming Jarret, FRS,FRSE, FRCVS, PhD, veterinary scientist: born Glasgow 2 January 1928; married 1952 Ann Fraser Sharp (deceased; two daughters); died 27 August 2011.