Atlas of Zoonotic Diseases in the South Caucasus

Abstract

Zoonotic diseases, which are infectious diseases transmitted to humans from animals, are an important cause of human morbidity and mortality. Individuals working in veterinary medicine and animal husbandry are at higher risk of acquiring zoonotic diseases due to their contact with animal hosts capable of carrying and disseminating a wide range of pathogens.  They may also spread these pathogens to community members, their families, and uninfected animals. Regional mapping of transmission risk for zoonotic disease presents an important tool to answer many human and animal health-related questions and is crucial for addressing areas of in-creased risk to humans and livestock. The South Caucasus (Armenia, Azerbaijan, and Georgia) exhibits high natural and social diversity, contributing to the persistent circulation of many zoonotic pathogens and the emergence of zoonotic diseases. Over the years, scientists from all three countries have developed a number of national atlases demonstrating territorial division, landscape, natural resources, and human population.  Here we present a cartographic atlas of the nature and distribution of zoonotic diseases in the South Caucasus. This is the first presentation of the spatial distribution of seven zoonotic diseases (anthrax, brucellosis, Crimean-Congo hemorrhagic fever, leptospirosis, plague, tick-borne encephalitis, and tularemia) that originate and persist in the natural environment. The goal of the Atlas is to identify and illustrate geographic, ecological, and social factors that drive the emergence, re-emergence, and persistence of pathogens in nature that are communicable to people and livestock. The information presented can be used to direct prevention and control efforts through-out the South Caucasus by identifying priority areas for targeted surveillance, livestock vaccination, and public health education campaigns. Such efforts reduce human transmission risk, contribute to the development of epidemiological assessment of disease burden, and improve programmatic planning and   management in the region. To add to a broader understanding of the distribution of zoonotic diseases in the region, we performed descriptive and analytical studies to identify reservoirs, vectors and risk factors for zoonotic infections. In an accessible way, we present the historical and current distribution of seven zoonotic diseases in Armenia, Azerbaijan and Georgia, as well as their epidemiological traits, regional and country population morbidity, and natural foci. The global movement of people, goods, and animals, as facilitated by trade and tourism, accelerates the spread of infectious diseases. Efficient, robust surveillance systems are essential for early detection and response.  Historical infection data, collected from 1950 to 2020, can help inform health networks in their early detection efforts and outbreak responses. Effective surveillance systems rely on accurate reporting and response capability at local and national levels. Early identification of zoonotic disease emergence is crucial for containing cases and out-breaks of this disease.  To develop the Atlas, we ac-quired historical information on the location, source, and impacted populations of different outbreaks and, by extension, identified other similar regions where their circulation may have gone undetected. The Atlas specifically acknowledges the broad range of determinants that impact patterns of infectious disease transmission. The Atlas aims to support the modernization of national surveillance and to identify areas at risk for various zoonotic pathogens in the South Caucasus. Zoonotic pathogens, their arthropod vectors, and vertebrate reservoirs are an integral part of the natural environment, but various ecological and social factors also influence the distribution of these pathogens. Medical geography tools analyze spatially referenced data on distributions of animal hosts, arthropod vectors, and infectious agents, and their spatial concordance with environmental and social parameters. The Atlas includes a series of maps presenting data on the landscape, climate, vegetation, fauna, demographic patterns, social factors affecting the interface between animals and people, data on the detection and identification of zoonotic agents in natural habitats, and incidence of human disease morbidity across South Caucasus.  The Atlas illustrates the regional heterogeneity in distribution of the infections concerning the mosaic of physical and cultural landscapes typical in the Southern Caucasus.  Finally, we identify areas where zoonotic diseases may occur in the future based on a high risk of spillover to humans, thus providing guidance on targeted surveillance efforts. The Atlas can be of use to geographers, environmental workers, epidemiologists, veterinarians, and public health specialists.

The study and publication of the Atlas was made possible by financial support provided by the US Defense Threat Reduction Agency in the frame of Grant #HDTRA11910044 – “PREPARATION OF THE ATLAS OF ZOONOTIC INFECTIONS IN THE SOUTH CAUCASUS”