Introductory Chapter: Why the Study of Zoonoses?

1. Introduction

Zoonoses are infectious diseases that are naturally transmitted between vertebrate animals and humans due to the close interaction between the two, with severe consequences for public health and significant economic losses for both the family and the nation. It is a complex group of pathologies caused by a great diversity of pathogens with diverse biological cycles and modes of dissemination. The health problem is such that zoonoses currently represent about 70% of infectious diseases of man (new and existing) in most countries, with more than 200 known types of these [1].

They are a complex group of diseases caused by a diversity of pathogenic microorganisms with varied biological cycles and modes of dissemination that constitute a real challenge for public health with full validity of their complexity and therefore the need to consider multiple perspectives for the approach, without a doubt, all related to epidemiology, biology, and social sciences; in this sense, it is essential to consider and develop integrated interventions that result from the knowledge of the process that defines zoonosis, objective of this book, that is, to show concepts, theories, and arguments about it that contribute to the understanding of such a complicated phenomenon [1].

2. Reasons for researching and studying zoonosis

At present, it is necessary to provide information to health sciences professionals, health authorities, and the general population on zoonosis; hence, the updating and condensation of the concepts that define this type of disease is imperative. Main objective of this book entitled: “Zoonosis of Public Health Interest,” because worldwide there has been an increase in the incidence and prevalence of zoonoses, and even the emergence and re-emergence of some of them are mainly due to the penetration of the human beings in territories with natural reservoirs of infection, climate and environmental change, the development of diagnostic methods with greater sensitivity and specificity, demographic factors such as migration, forced human displacement and population growth, international production and distribution of food, and the deficient sanitary programs destined to the control of these pathologies [2].

The information contained in this book can contribute in each country in the field of primary health systems with the evaluation of the epidemiological and epizootic panorama of the human and animal population as a key element of their epidemiological surveillance systems for the prevention and control of these diseases. These diseases are transmitted between animals and humans; therefore, quality, complete, and current data are provided on different facets or aspects that define the origin, approach, and control of zoonosis as pathologies of great interest to public health because they result from the close relationship between animal and human health, the difficulties that many countries, mainly those with low economic income, have in objectively determining the degree of affectation, and the imbalance caused by zoonotic diseases in the health system, and of course in the quality of life of the individual and the community [3].

This book makes clear the negative implications for public health (due to the high morbidity and mortality) of the relationship in the category of zoonosis between humans and animals, which goes beyond the simple transmission of pathogens, since the zoonosis is a complex process in which various factors converge, from the human sphere, among which epidemiological behavior, space, population, economy, social structure, and cultural order stand out [4]. In this sense, it corresponds to the health professional the interest in reviewing the written works that are produced on zoonoses, particularly due to the great composition that this type of pathology has that compromises animal and human health, and because these diseases are not approached with sufficient depth in the academic training programs of the health sciences sector, which translates into terrible confusion and ignorance about the mechanism of transmission, pathogenesis, diagnosis, treatment, prevention, and control of such fearsome pathologies [5].

This book shows investigations of different variables of zoonosis such as health risk, biological-environmental relationship, treatment, emergence of pathogens, health policies, and basic concepts on the transmission of diseases between animals and humans. Since, in the context of complex reality in which zoonosis moves, it is essential to study the factors that contribute to the current situation of these diseases in the world. So, it is a key to describe them from multiple perspectives, because in this order of ideas it stands out the appearance of new zoonotic diseases and the modification of the form of transmission of some existing ones that do not allow the explanation of the events for their adequate approach and can even generate wrong diagnoses. Hence, the information provided in this book points to the global epidemiological attack and with a comprehensive vision for being the one that ensures greater effectiveness in terms of population coverage and, therefore, in prevention and control [6].

In general terms, the importance of understanding and rigorous attention to the animal-man relationship in the genesis of diseases in the context of public health is described, with particular interest in areas or regions marked by poverty and poor services. Health and other factors on which the need to theoretically base the conceptual elements of zoonosis that are explicitly recorded in this writing is based, can contribute to the scientific planning of health between humans and animals in relation to the constants changes that occur in the dynamics of the transmission [7].

The exposed concepts can serve as tools to increase the response capacity of health systems for the development and implementation of plans and training programs for health personnel, as well as for health education to the population, in general, in terms of zoonosis, and specifically the experiences that are narrated can be used for the timely attention of endemic and epidemic foci for the follow-up of cases and for the implementation of an adequate information and epidemiological surveillance system [8]. In this sense, you are invited to carefully read the theoretical framework presented in this work.