Preface to the fourth edition

The layout and approach in this edition remains the same as in previous editions but the text has been revised and updated, with the biggest changes made to vector control procedures. Problems can, however, arise when advocating the use of named insecticides for control because some insecticides (acaricides) may be banned in some countries yet not in others. In general I have left it to the reader to find out what chemicals are allowed in his or her area of operation.

Two new transmission cycles on West Nile and Japanese encephalitis viruses have been incorporated in Chapter 3. However, the biggest change to this edition is the inclusion of 24 colour illustrations of some of the more important vectors and pest species. This it is hoped will help readers have a better appreciation of what various arthropods actually look like – and some may even find the photo of a Sabethes mosquito beautiful! Another change has been to return to the older classification of mosquitoes and place all relevant species in the genus Aedes; that is, Ochlerotatus is not recognized here as a genus. Apart from other considerations this will simplify matters for readers.