Immunologist who argued that smallpox vaccinations killed more than the disease

PROFESSOR GEORGE DICK, the immunologist who has died aged 82, waged a long war against the vaccination of children for smallpox, which he blamed for killing more victims than the disease.

By the 1950s smallpox was so rare in Britain that mass vaccination, even with its small risk of mortality, was killing more children than would have died without it. In 1962 Dick spoke out at the British Medical Association annual meeting against the smallpox vaccination programme enjoined by the Minister of Health, Mr Enoch Powell. "He is asking for a sacrifice of at least 20 babies a year," Dick said.

Dick's conclusion was that, for smallpox, "we should now give up routine infant vaccination and depend on epidemiological control". To cheers from his fellow doctors, Dick advised Mr Powell to spend "more effort on devising a plan to reduce the risk of importation of smallpox into Britain."

But it was not until 1971 that Sir Keith Joseph, as Secretary of State for Social Services, announced in a letter to all GPs that the government-backed programme encouraging vaccination for children was to be dropped. Dick had made known his opposition to childhood smallpox immunisation to the committee that advised Joseph to drop the programme.

Since then the disease has become extinct, not only in Britain but also, according to the World Health Organisation, throughout the world.

The other disease with which Dick's name is linked is poliomyelitis. There was a wide and justified fear of the disease in the 1950s, despite the success of vaccines developed by Jonas Salk in 1954. These vaccines were of the "dead" type, but there were hopes that a "live" vaccine could be produced which could be taken by mouth instead of by injection. But the danger with early oral vaccines was that the viruses might mutate and infect other people with a virulent disease that could lead to death or paralysis.

In 1956 Dick tried out a new kind of live vaccine on his four-year-old daughter, a decision which was reported soberly in the British Medical Journal but which caused a flutter of excitement in the tabloid press. But by 1958, after experiments on 200 volunteers, Dick came to the conclusion that the live poliomyelitis vaccines then available were not suitable for use on a large scale, because of the risk of spreading infection.

In 1962 Dick attacked (on the grounds that the live vaccine could spread the disease) government backing for a change to an oral Sabin live vaccine in place of the Salk vaccine. "We were the first country to dribble oral vaccine into the community," he complained.

Dick had more comforting opinions on another scare in the late 1950s. There was a fear that budgerigars might spread polio to their owners, after a boy died following a bite from a budgie on his lip. Dick tried to inoculate four budgies with polio germs. In each case they failed to contract the disease. Dick concluded that "the natural infection of these birds may prove to be a rare event", which turned out to be the case.

Dick also worked successfully on a combined vaccination that could give immunity for children to diphtheria, whooping cough, tetanus and poliomyelitis through two injections, one before the age of 12 months and the next at 18 months.

George Williamson Auchinvole Dick, a son of the manse, was born on Aug 14 1914, in Fife. He was educated at the Royal High School, Edinburgh, and Edinburgh University, where he read medicine.

He acted as assistant pathologist at the Royal Infirmary, Edinburgh, from 1939 to 1940. During the Second World War he served with the Royal Army Medical Corps in East Africa and Italian Somaliland. He ended the war as a lieutenant-colonel.

After the war Dick became a Foundation Fellow at the Rockefeller Institute, New York. He also became a Fellow at the Johns Hopkins University, Baltimore. In 1951 he returned from America to work for the Medical Research Council.

It was in the decade from 1955, when he was appointed Professor of Microbiology at the Queen's University, Belfast, that Dick did his most innovative work. He worked assiduously on poliomyelitis vaccines with a dedicated team at the Royal Victoria Hospital.

From 1965 to 1973 he was Professor of Pathology at the Middlesex Hospital Medical School (part of London University). In 1973 he moved to the Chair of Pathology at the Institute of Child Health - with connections to the Great Ormond Street Hospital - remaining there until his retirement in 1981.

He was popular and approachable, and, though more than 6 ft tall, was never aloof.

Dick's pre-eminence in his field was recognised internationally by a string of awards, including that of Hero of Public Health, given by the Johns Hopkins University.

A practical and down-to-earth man, Dick also wrote for the layman. His Health on Holiday (1982) prepared tourists for the Mediterranean sun.

Dick's learned papers covered a fine clutch of infectious diseases: yellow fever, Marburg's virus, hepatitis, rabies, whooping cough and subacute sclerosing panencephalitis.

He married, in 1941, Brenda Cook; they had two sons and two daughters.