Any disease or infection that is naturally transmissible from vertebrate animals to humans and vice-versa is classified as a zoonosis. The agents involved in this transfer can range from fungi and bacteria to viruses. They can make the 'jump' when the conditions are right i.e. the host animal is infected and the human comes in contact with the animal vector.
Below is a diagram illustrating the spread of the H5N1 virus which is another example of a zoonotic disease:
This diagram illustrates how H5N1 makes the jump to mammals and to the human population. Avian influenza is generally found in endemic waterfowl and shorebirds but can occasionally make the jump (by jump I mean can infect) to the domestic bird populations, namely chickens. These chickens then become the main vector for human exposure to H5N1, this is why Hong Kong, China has eliminated thousands of chickens during H5N1 outbreaks. Swine can also be infected with these avian flu viruses. One key point to note is that these vectors often don't die or appear sick due to mild symptoms presented during infection. The vectors can then stay alive while they are infected and can come into contact with the human population where the disease can be very deadly (greater than 50% mortality rate).
The following videos offer a much more complete explanation for H5N1 structure, transmission, virulence and pathogenisis:
(Above figure is an original figure)
Make it relatable a little more to the average layperson by quickly mentioning that H5N1 is a flu virus. This might be a perfect place to include a news article.
ReplyDeleteThis is really fascinating! I like the diagram. I'd like to see more examples of zoonotic diseases and some little case-studies on particular species affected by them.
ReplyDeleteThe diagram is great at explaining how h5n1 virus was transmitted to humans. If you're audience isn't aware of what the h5n1 virus, maybe finding and adding a video that isn't to long?
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