zoonoses and communicable diseases common to ... - PAHO/WHO

xiiPREFACE TO THE SECOND EDITIONnoted. Another topic deeply interesting to researchers is the mystery of the radicalantigenic changes of type A influenza virus, a cause of explosive pandemics thataffect millions of persons around the world. Evidence is mounting that thesechanges result from recombination with a virus of animal origin (see Influenza).That this should occur is not surprising, given the constant interaction between manand animals. As a rule, zoonoses are transmitted from animal to man, but the reversemay also occur, as is pointed out in the chapters on hepatitis, herpes simplex, andmeasles. The victims in these cases are nonhuman primates, which may in turnretransmit the infection to man under certain circumstances.Among emerging zoonoses we cite Lyme disease, which was defined as a clinicalentity in 1977; the etiologic agent was found to be a spirochete (isolated in 1982),for which the name Borrelia burgdorferi was recently proposed. Emerging viralzoonoses of note in Latin America are Rocio encephalitis and Oropouche fever; thelatter has caused multiple epidemics with thousands of victims in northeast Brazil.Outstanding among new viral disease problems in Africa are the emergence of Eboladisease and the spread of Rift Valley fever virus, which has caused tens of thousandsof human cases along with great havoc in the cattle industry of Egypt and has evokedalarm around the world. Similarly, the protozoan Cryptosporidium is emerging asone of the numerous agents of diarrheal diseases among man and animals, and probablyhas a worldwide distribution.As the English edition was being prepared, reports came to light of two animaldiseases not previously confirmed in humans. Three cases of human pseudorabiesvirus infection were recognized between 1983 and 1986 in two men and one womanwho had all had close contact with cats and other domestic animals. In 1986, serologictesting confirmed infection by Ehrlichia canis in a 51-year-old man who hadbeen suspected of having Rocky Mountain spotted fever. This is the first knownoccurrence of E. canis infection in a human. These two diseases bear watching aspossible emerging zoonoses.The space given to each zoonosis is in proportion to its importance. Some diseasesthat deserve their own monographs were given more detailed treatment, but noattempt was made to cover the topic exhaustively.We, the authors, would like to give special recognition to Dr. Donald C. Blenden,Professor in the Department of Medicine and Infectious Diseases, School ofMedicine, and Head of the Department of Veterinary Microbiology, College ofVeterinary Medicine, University of Missouri; and to Dr. Manuel J. Torres, Professorof Epidemiology and Public Health, Department of Veterinary Microbiology,College of Veterinary Medicine, University of Missouri, for their thorough review ofand valuable contributions to the English translation of this book.We would also like to recognize the support received from the Pan AmericanHealth Organization (PAHO/WHO), the Pan American Health and EducationFoundation (PAHEF), and the Pan American Zoonoses Center in Buenos Aires,Argentina, which enabled us to update this book.We are most grateful to Dr. F. L. Bryan for his generous permission to adapt hismonograph “Diseases Transmitted by Foods” as an Appendix to this book.