Experiments on animals

of variation in response among species reliance on animal data may confuse clinical findings and thereby prove a wasteful detour. For instance, smoking and excessive alcohol consumption are major causes of morbidity and mortality in Western society, but attempts to reproduce many of their harmful effects in laboratory animals have met with little success. It has proved virtually impossible to induce lung cancer in animals by forcing them to inhale smoke,2 and the cause of alcohol induced liver cirrhosis has been doubted owing to failure to produce similar effects with alcohol in all common laboratory animals. Only the baboon reacts in a similar way to humans,4 and even this finding has now been disputed.' More could be achieved by reallocating resources to methods directly relevant to people, such as epidemiological, clinical, and necroscopic studies; work with healthy volunteers; and in vitro experiments with human cells and tissues. Indeed, progress by the study of humans is by no means unusual-it is more nearly the rule.5 Unfortunately, human based research requires more skill and patience to avoid unnecessary risks whereas animals are still regarded as disposable. Even research that has come to rSly on animals would not be halted by stopping the experiments as scientists would quickly devise new techniques to achieve their objectives. Historically, the lack of an animal model for cholLra6 and yellow fever7 did not stop research but forced investigators to concentrate on (ultimately more relevant) clinical and in vitro studies to identify the modes of transmission of these diseases so that eradication campaigns could be started. The use of animals to test the potency of vaccines is traditional, but such an approach is of no value in assessing pneumonia vaccines because the causal organisms are generally not virulent in laboratory animals. Once again the lack of an animal model was the incentive to develop a successful and humane alternative based on chemical analysis and studies with human volunteers.' The key to eliminating animal experiments lies in providing the necessary incentives. I hope that researchers do not react defensively but recognise the value to humans and animals of a more relevant approach to medical research and health care.