Synthesizing the connections between environmental disturbances and zoonotic spillover

Abstract

Zoonotic spillover is a phenomenon characterized by the transfer of pathogens between different animal species. Most human emerging infectious diseases originate from non-human animals, and human-related environmental disturbances are the driving forces of the emergence of new human pathogens. Synthesizing the sequence of basic events involved in the emergence of new human pathogens is important for guiding the understanding, identifi cation, and description of key aspects of human activities that can be changed to prevent new outbreaks, epidemics, and pandemics. This review synthesizes the connections between environmental disturbances and increased risk of spillover events based on the One Health perspective. Anthropogenic disturbances in the environment (e.g., deforestation, habitat fragmentation, biodiversity loss, wildlife exploitation) lead to changes in ecological niches, reduction of the dilution effect, increased contact between humans and other animals, changes in the incidence and load of pathogens in animal populations, and alterations in the abiotic factors of landscapes. These phenomena can increase the risk of spillover events and, potentially, facilitate new infectious disease outbreaks. Using Brazil as a study model, this review brings a discussion concerning anthropogenic activities in the Amazon region and their potential impacts on spillover risk and spread of emerging diseases in this region.

Editorial: Soil-transmitted helminth infections from a One Health perspective

“…Deforestation of tropical forests and habitat fragmentation facilitate the dissemination of several viral, bacterial, and parasitic diseases. By contrast, the preservation of biodiversity and the environment is a protective factor against emerging infectious diseases ( 4 ). Currently, there is a growing acceptance of the One Health need to address parasitic diseases in the next decades in a changing, conflicted, and resource-limited world ( 5 , 6 ).…”

Emergence of zoonotic Brugia pahangi parasite in Thailand

“…Brugia pahangi is not only transmitted among the animal reservoirs (domestic dogs or cats) but also switching the animal reservoir hosts so-called “zoonotic spillover” [ 34 , 35 ]. Zoonotic spillover requires intertwined interactions that can sustain transmission of enzootic parasites between the animal reservoir population (domestic dogs and/or cats) and the local vector population.…”

Editorial: Host-virus interaction at the omics and ecology levels

“…The intensification of driving forces of spillover events (transmission of pathogens from animal species to humans) facilitates new viral outbreaks and pandemics. Specifically, environmental changes and social issues (e.g., deforestation, biodiversity loss, bushmeat consumption, unplanned urbanization, intensive farming) increase the chances of humans and animals sharing pathogens ( 3 , 4 ). Also, the transmission and pathogenesis of viruses are mediated by host components (e.g., immune and genetic factors, microbiome) and viral factors (e.g., transmissibility, replication characteristics, virulence) ( 5 – 7 ), and this information highlights the importance of deciphering host-pathogen interactions in the context of viral diseases.…”