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Sickness. humans vs animals

  1. Apr 23, 2007 #1
    Everyone knows about mad cow disease and rabies the many different diseases the farm animals and pets we carry around with us have developed but do free animals with little contact with humans also get diseased alot?

    we humans gets sick between 2-3 times per year. (average)
    i have seen pets go years without getting sick.

    why are we sick more often? are we too clean?
    do we clean of so much bacteria that our immune system dont get enough practice or something?

    im no scientist, but i would like to know the answer to that one.
  2. jcsd
  3. Apr 23, 2007 #2

    jim mcnamara

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    Staff: Mentor

    By animals you seem to mean "mammals", so I'll stay with them.

    Mammals in a population, say, deer, are subject to lots of diseases. The main reasons truly wild deer do not run around looking sick is:
    1. they are favored targets of predators because they are easy to catch
    and are attacked by coyotes or local feral dogs.
    2. sick animals tend to stay hidden because of reason #1.

    Pets, kept largely inside, away from other pets of the same species
    to "play" with, are not exposed to pathogens (disease causing agents like viruses and bacteria) like us humans are. How many times has someone near you sneezed or coughed in your direction?

    Go to your local SPCA, or Animal Humane location, and ask what they have to do to keep the animals in the shelter healthy. They do a lot of cleaning, to slow the spread of disease. Sometimes when, for example, dogs are infected with parvovirus, they have to put the animal "solitary" confinement well away from all others. A lot of animal shelters require you to step in a special germ-killing footbaths before you enter or leave those special areas.

    Every mammal has a long list of diseases it can catch, a lot of them are potentially fatal, as well.
  4. Apr 23, 2007 #3


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    Staff Emeritus
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    Gold Member

    Yes, animals in the wild catch and carry many diseases, and those that aren't killed by predators generally die of these diseases. It is rare that an animal in the wild will die of "old age" rather than through predation, starvation or disease.

    Rabies is much more of a wild animal problem than a domestic animal problem nowadays due to the vaccination of domestic animals, at least in the U.S.

    In addition to viral and bacterial diseases, wild animals also are often heavily infested with parasites, which can also kill them if the parasite burden gets too heavy.
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