• Question: how serious can most diseases be in London?

    Asked by les science est tres cool to Rosie, Beccy on 12 Jun 2017.
    • Photo: anon

      anon answered on 12 Jun 2017:

      We are susceptible to the same diseases as people who live elsewhere but we have a lot of advantages.

      Firstly we have the NHS. That means that everyone, even poor people, can go to the doctor or hospital without worrying how much it will cost them. (Of course, the NHS costs money, but we all collectively pay taxes so everyone pays in while we work so that it’s there when we need it.)

      We also have vaccination programmes which means that you aren’t likely to get polio or measles (although there is still measles transmission in the UK because some people don’t get vaccinated). We also don’t have certain mosquitoes that spread certain viruses. The Aedes aegypti mosquito spreads dengue virus and Zika virus. It’s too cold here for Ades aegypti so we don’t have to worry about that.

      But some diseases are very hard to stop – influenza for example. It is highly infectious and it is respiratorily transmitted (from people coughing out droplets with virus in them) and so it is very hard to stop. There is flu vaccine but the flu virus changes so rapidly that sometimes serious flu strains aren’t stopped by the flu vaccine for a particular year.

      Ebola is dangerous as an infection anywhere, but we don’t have the bats that carry the virus so the only way that we can have Ebola in the UK is if someone catches it in an affected country (such as in West Africa in 2014) and comes into the UK infected. This happened with some healthcare workers but they were carefully monitored when returning from Ebola-affected areas to make sure they didn’t cause outbreaks in the UK.

    • Photo: Rosie Fok

      Rosie Fok answered on 12 Jun 2017:

      There are lots of different factors that make an infection serious: the microganism (its virulence, or ability to cause disease), the host (the person who gets the infection, e.g. are they malnourished, are they having to sleep out in the cold, do they have a problem with their immune system), the sanitation and hygiene available (will it spread from person to person, will other people come into contact with infectious bodily fluids) and the healthcare system (are the population vaccinated, is there access to good medicine and supportive measures in a hospital). Some of these factors mean that we just don’t see certain infections in a rich country like the UK, or an urban environment like London. But, some viruses and bacteria can cause devastating disease wherever you live, for example meningococcal septicaemia or influenza in pregnant women. As Christl says, vectors (the route by which a disease is carried from one human to another) are really important too (so if we don’t have the right mosquitoes, some infections won’t get transmitted on in London).