Bio 8B Flashcards
emergence of pathogens
what is the emergence of pathogens?
An infectious disease that is new to the human population (emerging) OR is rapidly increasing in incidence (re-emerging)
what is a non-infectious disease?
a disease not caused by a pathogen
- caused by abnormal genes or lifestyle factors resulting in disease
what is an infectious disease?
a disease caused by a pathogen
- contagious
- how easily the disease can be transmitted and spread between people
- virulent
- how severe the disease that the pathogen causes
what is an emerging pathogen?
a disease that:
- Has not occurred in humans before
- Have occurred previously but only affected particular populations in isolated places
- Have occurred throughout history but have only recently been recognised as being caused by pathogens
what is a re-emerging pathogen?
a disease that:
- was once a major public health problems and then declined rapidly in incidence BUT then again become health problems for a large number of people
where do emerging and re-emerging diseases come from?
evolution of causative organism:
- the pathogens causing disease can evolve to either infect humans, or, if previously capable of infecting humans, evolve to evade treatments by acquiring resistance
globalisation and travel:
- due to our ability to quickly travel around the world, diseases that would otherwise have remained localised to a specific area can quickly spread to multiple countries
increased exposure of humans to animals:
- as the human population grows anfd climate change alters the environment, humans are more likely to come into contact with animals.
increasing human populationL
- larger populations lead to increased population densities in cities, increasing the likelihood of a disease spreading and causing large scale health problems for a population
changing technology:
- new technology can be responsible for the emergence or re-emergence of a disease
- e.g. pathogens spread through air conditioners
insufficient vaccination of the population:
- previously managed diseases can re-emerge if the proportion of a population that is vaccinated against the disease decreases
- loss of herd immunity HENCE more people are likely to be susceptible to the disease + encountering the pathogen
what is zoonosis?
a disease caused by a pathogen that has been transmitted to humans from another species
what are the types of disease outbreaks?
endemics:
- When a disease occurs at a relatively constant baseline (low-ish) level in a population
epidemics:
- Sudden, widespread increase in the occurrence of an infectious disease among a specific population in a specific location at a particular time
pandemics:
- Epidemics that have spread to different countries and/or continents
- Affect a greater number of people (compared to epidemics)
- More difficult to control
