The WHO programme for prevention and control of viral, chlamydial, and rickettsial diseases. Brief review.

Through the advancement of biological and medical sciences and the application of modern technology, the disease burden imposed by viral, chlamydial and rickettsial disease has steadily decreased. Smallpox has been eradicated, poliomyelitis is under control in many countries, and measles, mumps and rubella viruses may eventually be eliminated in many developed countries. New and improved vaccines have also recently become available for rabies and hepatitis. These are major advancements. Not to be overshadowed however, are the developments which may lead to the prevention or control of other infectious diseases. For many agents, recently acquired knowledge relating to virology, replication, structural and genetic characteristics, and host responses to infection pave the way for disease intervention in numerous ways. For other agents, recent advances in molecular biology make possible new classes of effective vaccines. It is crucial that these advances be incorporated as soon as possible into effective public health programmes for developing as well as developed nations. Much work yet remains, particularly in the prevention and control of respiratory diseases, diarrhoeal diseases, vector-borne diseases and hepatitis. The WHO Viral Diseases Programme has a major role in supporting laboratory and field research on new technologies and intervention strategies, in disseminating technological advances through teaching and training, and in translating the newer knowledge into action programmes for the prevention and control of viral, chlamydial and rickettsial diseases.