What are some examples of emerging infectious diseases?
- Lassa Fever
- Ebola Hemmorhagic Fever
- Legionnaires' Disease
- Lyme Disease
- Hantavirus Pulmonary Syndrome
What are some examples of Re-emerging infectious diseases?
- Yellow Fever
First Transition that allows emerging diseases to develop
- Occurs when people begin to live in much closer proximity to one another
- Proximity between populations allows for easy transmission of disease
Second Transition that allows emerging diseases to develop
- Neighboring civilizations made contact with each other through war or trade
- Contact allowed the exchange of pools of infectious organisms and vectors between populations.
Third Transition that allows emerging diseases to develop
Worldwide exploration and colonization led to the identification of new populations
Newly identified populations came into contact with pathogens never seen before within their cultures.
Fourth Transition that allows emerging diseases to develop
- This is happening now. Ongoing causes are:
- Global urbanization
- Increase in population density
- Social upheaval
- Long distance trade
- Technology development
- Land clearance
- Climate change
What are the three ways a virus can change?
Mutation (every replication)
- A virus infects a cell, there will be mutations that can occur.
- Usually, cells have a way of proof-reading DNA and ususally mutations get caught.
- Occasionally they won’t and new cells get stuck with that mutation. The same happens with viruses. New viruses have a mutation, possibly the mutation changes one of the proteins that it needs to replicate, etc. Sometimes these mutations elicit a brand new virus.
- Rare event
- It requires one cell to be infected with two different viruses. DNA replicates for both viruses, genetic material recombines, the 2 get mixed. But there is only a little of the DNA that is mixed.
- Happens during coinfection of 2 viruses
- Like recombination except there are whole segments changing and mixing.