ABSTRACT:
Zoonotic diseases, which are transmitted between animals and humans, comprise over 60% of emerging infectious diseases globally. Their rising prevalence is closely linked to ecological disruption, urban expansion, wildlife trade, and increased human-animal interaction. This review explores the multifaceted nature of zoonotic disease emergence, focusing on transmission pathways direct, indirect, and environmental as well as the critical role of reservoir and amplification hosts. It examines the evolutionary mechanisms that enable pathogens to adapt to new hosts, such as genetic mutation, reassortment, and selection pressures, with case studies including influenza, Ebola, and SARS-CoV-2. The global health implications are vast, encompassing public health system strain, increased morbidity and mortality, and significant economic losses. The review emphasizes the significance of the One Health approach, which links human, animal, and environmental health domains. Furthermore, it discusses challenges in vaccine development and outlines preventive strategies including early warning systems, genomic surveillance, public hygiene education, and global policy coordination. Together, these insights contribute to better pandemic preparedness and inform holistic strategies to mitigate the risk of future zoonotic outbreaks.
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