Professor Rodrigo Zeledon is a retired professor in Medical Parasitology, Zoonotic Diseases at the University of Costa Rica. He graduated at the Johns Hopkins School of Hygiene and Public Health as Doctor of Science, He published 5 books, 4 monographs, 15 book chapters and more than 240 papers on medical parasitology. Dr. Charles B. Beard is Chief Bacterial Diseases at the National Center for Infectious Diseases, Forl Collins, CO, USA and Associate Director for Climate Change, at the National center for Emerging and Zoonotic Infectious Diseases, Atlanta, CO, USA.He holds a PhD in Medical Parasitology and Entology University of Florida, Gainesville, FL. He has an Experts appointment at the WHO, International Health Regulations Roster till June 2012. David Leiby is Professor at the George Washington University, Department of Microbiology and Tropical Medicine. He is head of the Transmissible Diseases Department at the American Red Cross, Rockville, MD. He is co-chair of the Technical Group on Diagnostics test for screening and diagnosis of Trypanosoma cruzi Infections at WHO. Patricia L. Dorn, is Professor at the Department of Biological Science of the Loyola University in New Orleans.

• Dedication 1. Introduction and historical background. 2. Triatomine vectors. 3. Animal reservoirs. 4. The parasite. 5. Prevalence of Chagas disease in human beings. 6. Final remarks.Acknowledgements References

Professor Rodrigo Zeledon is a retired professor in Medical Parasitology, Zoonotic Diseases at the University of Costa Rica. He graduated at the Johns Hopkins School of Hygiene and Public Health as Doctor of Science, He published 5 books, 4 monographs, 15 book chapters and more than 240 papers on medical parasitology. Dr. Charles B. Beard is Chief Bacterial Diseases at the National Center for Infectious Diseases, Forl Collins, CO, USA and Associate Director for Climate Change, at the National center for Emerging and Zoonotic Infectious Diseases, Atlanta, CO, USA.He holds a PhD in Medical Parasitology and Entology University of Florida, Gainesville, FL. He has an Experts appointment at the WHO, International Health Regulations Roster till June 2012. David Leiby is Professor at the George Washington University, Department of Microbiology and Tropical Medicine. He is head of the Transmissible Diseases Department at the American Red Cross, Rockville, MD. He is co-chair of the Technical Group on Diagnostics test for screening and diagnosis of Trypanosoma cruzi Infections at WHO. Patricia L. Dorn, is Professor at the Department of Biological Science of the Loyola University in New Orleans.

• Dedication 1. Introduction and historical background. 2. Triatomine vectors. 3. Animal reservoirs. 4. The parasite. 5. Prevalence of Chagas disease in human beings. 6. Final remarks.Acknowledgements References

Professor Rodrigo Zeledon is a retired professor in Medical Parasitology, Zoonotic Diseases at the University of Costa Rica. He graduated at the Johns Hopkins School of Hygiene and Public Health as Doctor of Science, He published 5 books, 4 monographs, 15 book chapters and more than 240 papers on medical parasitology. Dr. Charles B. Beard is Chief Bacterial Diseases at the National Center for Infectious Diseases, Forl Collins, CO, USA and Associate Director for Climate Change, at the National center for Emerging and Zoonotic Infectious Diseases, Atlanta, CO, USA.He holds a PhD in Medical Parasitology and Entology University of Florida, Gainesville, FL. He has an Experts appointment at the WHO, International Health Regulations Roster till June 2012. David Leiby is Professor at the George Washington University, Department of Microbiology and Tropical Medicine. He is head of the Transmissible Diseases Department at the American Red Cross, Rockville, MD. He is co-chair of the Technical Group on Diagnostics test for screening and diagnosis of Trypanosoma cruzi Infections at WHO. Patricia L. Dorn, is Professor at the Department of Biological Science of the Loyola University in New Orleans.

• Dedication 1. Introduction and historical background. 2. Triatomine vectors. 3. Animal reservoirs. 4. The parasite. 5. Prevalence of Chagas disease in human beings. 6. Final remarks.Acknowledgements References