[Vaccines and developing countries].

Infectious diseases are the main cause of mortality and morbidity in developing countries. The Expanded Programme on Immunization, initiated by WHO in 1974, now reaches 60 mill. a year at a cost of less than 2 US $ per immunized child, and saves 2.2 mill. lives annually. The present vaccines, however, have significant shortcomings. Measles vaccine is given too late to prevent the large number of deaths occurring in the first year of life. Attenuated polio vaccine has to be given three times and inherits the risk of "vaccine palsy" and revertion to virulence. Tetanus vaccine given to children does not prevent neonatal tetanus, the main cause of tetanus casualties. BCG does not control spread of tuberculosis. Vaccines given parenterally involve some risk of spread of HIV, and some potentially useful vaccines are too expensive for developing countries. By only modest investments modern gene technology could give improved and new vaccines which would potentially save 20 mill. lives a year. Particularly promising is the recent development of multi-vaccine-vectors. However, poor prospects for profit in developing countries and patent "swapping" by commercial producers severely hamper development in the vaccine field.