Zoonoses and emerging diseases Flashcards
what are ecosystem services
Benefits provided by ecosystems that contribute to making human life possible and worth living, including resources, regulation, and cultural and support services.
define zoonosis
Diseases that can be transmitted between animals and humans, such as rabies and avian influenza.
What is a vector
An organism, like a mosquito or tick, that transmits a pathogen between hosts but does not itself become infected.
What is a reservoir
Maintenance host populations that harbor a pathogen and serve as a source of infection for other target populations.
How do hosts differ from reservoirs
Hosts are organisms infected by a pathogen, while reservoirs sustain the pathogen and can infect other hosts.
What is the distinction between a pathogen and a disease
A pathogen is the causative agent, whereas a disease is the manifestation of the host’s response to the pathogen.
What are the major reasons for emerging infectious diseases
Globalization, population growth, environmental changes, and behavioral shifts.
How does globalisation contribute to disease emergence
Increased travel and trade facilitate the spread of pathogens across borders.
Give an example of environmental change leading to disease emergence
Deforestation, which disrupts ecosystems and brings humans into closer contact with wildlife reservoirs of pathogens (e.g., Ebola).
How does population growth influence disease emergence?
Denser populations increase human-animal interactions, creating more opportunities for zoonotic spillovers.
Why do pathogens evolve virulence?
To maximize transmission, often balancing between host survival and pathogen reproduction.
How can host-pathogen coevolution affect virulence?
Over time, a pathogen may evolve to become less virulent to sustain its host population.
Give an example of virulence evolution in a pathogen
The attenuation of myxoma virus in rabbits, where the virus became less lethal over time to sustain transmission.
How can ‘One Health’ principles aid in infectious disease surveillance?
By integrating human, animal, and environmental health data to detect and respond to emerging threats early.
What role do ecosystem services play in disease control?
Healthy ecosystems can regulate pathogens naturally, reducing disease risks (e.g., wetlands filtering waterborne diseases).
