Publisher's Synopsis
With the intensive use of DDT in the 1950s, tropical diseases were reduced to a minimum but not eradicated. They returned, having developed encreased multiple resistance of the vector insects to most chemical insecticides. The high doses of chemicals necessary caused levels of environmental contamination which were dangerous for man and animals. The use of environment-friendly materials for vector control initiated an intensive search for new biological factors able to support or replace some chemical treatments. As a result there are broadening applications of microbial preparations with bacillus thuringiensis and B. sphaericus for control of mosquitoes, blackflies and other vectors. Intensifying the search for new pathogens in nature which may be more efficient than those we know is the important task in the target countries of tropical diseases but also in other parts of the world. Efficient biological factors are rare and disappear soon after they have destroyed all available susceptible hosts. Therefore a search for new active organisms is important.;The intention of this manual is to help field workers with different aspects of the field handling of interesting new pathogens and parasites, based on the experience of the collaborating centres. This book is intended as a field guide for the search for new organisms.
