Alternative strategies for the control of epidemics of SLE and western equine encephalitis are considered in detail elsewhere (Reeves and Milby, 1990). In the event of an epidemic caused by one of these enzootic viruses, the control of adult vectors is probably the best approach for stopping the spread of disease. To be successful, it has been estimated that pesticide application should achieve a 90 percent or greater reduction in the infected vector population (W. Reeves, Professor of Epidemiology Emeritus, School of Public Health, University of California at Berkeley, personal communication, 1992).
As in the drug arena, resistance to pesticides can present serious problems to disease control. Mosquitoes, flies, and other disease-carrying insects have relatively short life cycles and produce many generations per year. This is a major factor in the development of pesticide resistance, and it is usually in these groups that resistance to a given chemical is seen. There are many strategies that can be used to delay or prevent pesticide resistance. So-called pesticide resistance management can include the rotation of chemicals, avoidance of sublethal doses, and the use of biodegradable materials. More research is needed, however, to hone the usefulness of these approaches.
The committee recommends that additional priority and funding be afforded efforts to develop pesticides (and effective modes of application) and other measures for public health use in suppressing vector-borne infectious diseases.
The areas of public education and behavioral change in relation to emerging infectious diseases currently show visible activity; the media, for example, have been presenting information to the public about the control of Lyme disease and HIV transmission. The committee was not constituted to address these two issues; however, because the topics represent potentially important aspects of emerging infectious disease prevention and control, it was considered appropriate to address them briefly here.
Public policy discussions and scientific efforts sometimes focus on vaccine and drug development and fail to give appropriate consideration to education and behavioral change as means for preventing and controlling infectious diseases. This is unfortunate, since it is often only by changing patterns of human activity—from travel and personal hygiene to sexual behavior and drug abuse—that the spread of disease can be halted.
For many infectious disease problems, however, particularly those that result from emerging microbes, the use of vaccines and drugs is not practical. Often, for newly recognized diseases, the causative agent is unknown,