Emerging zoonotic diseases originating in mammals: a systematic review of effects of anthropogenic land-use change

Abstract

1. Zoonotic pathogens and parasites transmitted from vertebrates to humans are a major public health risk with high associated global economic costs. The spread of these diseases accelerates with anthropogenic land-use changes (LUC), like deforestation, urbanisation and agriculture, factors that are expected to increase in the future due to human population expansion and increasing demands for resources. 2. We systematically review the literature on anthropogenic LUC and zoonotic diseases, highlighting the most prominent mammalian reservoirs and pathogens, analysing trends in publications and identifying avenues for future research.

3. The number of publications increased over the past three decades. The majority of studies were global reviews that did not focus on specific taxa. South America and Asia were the most studied regions. The most studied mammalian taxa were rodents, livestock and carnivores, while the most studied LUC was urbanisation. Associations were identified between hosts and type of LUC, and hosts and pathogens. 4. Research into specific animal reservoirs has improved our understanding of how zoonotic diseases spread with LUC. Host behaviour can be altered when their habitats are changed, which in turn impacts the pathogens they carry and the probability of disease spread to humans. Understanding this has enabled the identification of factors that would alter the risk of emergence, like virulence, pathogen diversity or ease of transmission, and the pathogens most likely to emerge, though many pathogens have not been studied yet. 5. Predicting how zoonotic diseases emerge and spread in response to anthropogenic LUC requires more empirical and data synthesis studies that link host ecology and responses to LUC with pathogen ecology and disease spread. The link between anthropogenic impacts on the natural environment and the recent COVID-19 outbreak highlights the urgent need to understand how anthropogenic LUC affects the risk of spillover and spread of mammalian zoonotic diseases