• Question: why are animals immune systems so strong compared to humans? the rarely get sick compared to humans but they are way less hygienic!

    Asked by 286genp45 to Remsha, Oliver, Lisa, Fiana, David, Kieran on 7 Nov 2018.
    • Photo: Kieran

      Kieran answered on 7 Nov 2018:

      Now this might be the best question I have received. So interesting, and you know, very few people appreciate how valuable understanding the immune system of animals actually is.

      You are right, they are less hygenic, but many people argue that we are TOO hygenic. Really what makes us sick are accidental ‘passengers’; bacteria or viruses that our immune systems havent seen before. So if you are constantly exposed to low level bacteria, you can become resistant to them, and that is why dogs for example dont get sick. Their immune systems have evolved to cope with bacteria that are foreign to us, and so our immune system can go into overdrive when it meets them.

    • Photo: Remsha Afzal

      Remsha Afzal answered on 7 Nov 2018:

      This was indeed such a thought provoking question! Kieran explains it very nicely when he said that part of the problem is that we try to be too hygienic, so much that our immune system doesn’t get a chance to be exposed to bacteria/viruses which would help our immune system develop better tolerance. Therefore, once our bodies do experience an invader, our immune system just cant handle it.
      However, I also would like to point out another fact that we appear to be very different to most animals in our level of socializing and crowding. Most of us now live in cities (a lot of the cities can be overpopulated). And so we are constantly exposed everyday to many possibly infected humans or contaminated surfaces per day. Of course, in such a lifestyle being clean and hygienic is important to stop constant epidemics from spreading. If you think of other big animals now that live like us in big colonies, like bats, they can get devastating epidemics!  So another idea is that our weakness in front of disease is because we are constantly exposed to bad bacteria/viruses because of living so close together to each other and handling contaminated surfaces that animals in the wild don’t. Similarly, a family pet isn’t usually found in a crowded situation with other members of its species. Interestingly, I also read that sheep who live like humans (in tightly packed quarters and indoors), have a lot more health problems like eye infections and lung problems than sheep who live in fresh air with plenty of space.
      Finally, maybe we just don’t realize when animals are sick because they don’t act the same way as we do when we get sick? Just a thought 🙂 What do you think?