Anti-vivisection campaigners, describing themselves as the Animal Liberation Front, attacked the homes of five scientists in Oxford and Cambridge last weekend. One victim was Sir Richard Doll, the eminent former Regius Professor at Oxford. "Vivisection is Murder" was painted in large letters on the front of his house and his car was sprayed with paint-remover
The attacks have brough genuine fear into the lives of their victims, so much so that the author of this article, a leading professor in the faculty of medicine at London University, has asked to remain anonymous...
The estimated death toll from smallpox in 1967 was about two million a year. Yet by 1980, using a vaccine prepared from virus grown on the skin of animals, smallpox was eradicated throughout the world. Work with animals is not an attractive feature of medical research nor is it welcomed by researchers. But experiments are generally controlled by qualified medical and veterinary Home Office inspectors and are conducted only under licence.
Tests with cosmetics and cigarettes are often cited as examples of cruel experiments on animals - but the enormous success they bring to the eradication of both human and animal diseases is overlooked. Protective immunisation is one example. The development and safety testing of drugs, vaccines and hormones would have been impossible without experiment and cell cultures derived from animal and human tissues.
Until recently, the only vaccines available against rabies - still widely used in many parts of the world - were produced in healthy animal brain and spinal cord. The new type of vaccine produced in tissue culture requires by law a safety test in animals to ensure freedom from residual live virus.
Vaccines against poliomyelitis, measles and, recently, hepatitis were only developed because of work initially carried out with monkeys. There are about 200 million carriers of hepatitis B and at least 3,000,000 babies in South East Asia alone acquire the infection at birth.
Many of these children will become carriers and develop severe liver damage, including liver cancer. Without the chimpanzee, a species in which experimental infection is usually trivial and without symptoms, vaccines could not be developed.
One of the more emotive issues in Britain in the Seventies was the protection of young children against whooping cough. The development of a vaccine was made possible only by the use of the mouse. Today every batch of vaccine must be inoculated into mice to ensure a protective effect and to reduce any complicating side-effects.
It is a World Health Organisation recommendation and a statutory legal requirement on health authorities that each batch of certain vaccines be tested in animals. It is a legal requirement, for example, that polio vaccines must be tested by injection into monkeys in order to exclude batches of vaccine which occasionally cause paralysis in children. Similarly, the method of inactivation of hepatitis B vaccines must be shown to be effective by inoculation of susceptible chimpanzees.
There have also been benefits for animals. Several examples suffice: canine hepatitis, with a mortality of 10-25 per cent in dogs, can be prevented by vaccination, as can dog distemper, which is a highly contagious air-borne infection. A vaccine prepared by treating infected tissue suspensions has been used successfully to protect kittens against a form of gastroenteritis which has a death rate of 65-90 per cent in cats.
Foot and mouth disease, which is highly contagious and often controlled by a policy of slaughter, is being replaced in many countries by a policy of vaccination. This decade will also see in Britain the eradication of brucellosis in animals and man as a result of vaccine development and public health measures. The list can be easily extended to transplantation immunology of kidneys, heart and liver, the understanding of rheumatoid arthritis and allergies, and the study of the relationship between immunity and cancer.
As to the future, to cite only a few examples, vaccines to prevent malaria, dental caries and sexually-transmitted diseases are under development, while multiple sclerosis, other brain diseases and the management of cancer are under investigation. Progress in all these subjects depends on work with animals, as was the successful treatment of diphtheria in the past and the development of BCG vaccines against tuberculosis.
The real moral issue is whether man is justified in conducting animal experiments to protect his own species. Animal health and welfare have obviously also benefited enormously from such experiments. It is difficult to discount the relationship and bonds that exist between man and his animals. Many of us have animals as pets - and, believe me, it is upsetting to consider any form of experiment on animals. But I believe that the advantages override these painful considerations.
