The causative agents of disease reach human beings by passing through environments formed by diverse cultures. These cultures affect both the pattern of the disease and the ease and efficacy of control measures. In developing countries there are problems of controlling specific diseases (such as smallpox, leprosy, and tuberculosis) spread by or within population groups that are socially but not geographically isolated. The cultural values of some socially isolated groups may provide a distillate of the values that are more widely diffused in the general population, and thus provide profitable study for public-health planners and practitioners. The converse proposition is that some specific communicable diseases may strongly affect culture, including social structure. The social response to endemic leprosy and widespread tinea imbricata has been stratification of apparently homogenous populations into two distinct social groups. If continued, the effect of this process will be to concentrate and isolate any genetic factors that may be associated with these diseases. The effect of modern cultural change in these situations so far has been to add to the social disabilities of the sufferers.
Present address: Department of Preventive and Community Medicine, Faculty of Medicine, University College, Nairobi, Kenya.