This book has been written to sensitize the Public on the Influence that insects have on Occupational Health worldwide. The blood-sucking insects of great Public Health concern belong to the Class Insecta. These have been discussed together with a few species of Economic importance. Further, the author thought that this book may benefit Physicians and other Health specialists who do not need detailed entomological knowledge on insects of Public Health importance. In addition, special emphasis has been placed on the Epidemiologic importance of Disease-Agents Transmission Dynamics by adult insects, in the course of obtaining blood meals. In addition, the book may benefit student Nurses,students of Human and Veterinary Medicine, Bio-medical Sciences, General Medical practitioners and Health Researchers in Occupational Health, Public Health, International Health, Community Health, Community Medicine, Vector-Borne diseases, Cognitive Psychologists and Psychiatrists.