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Cholera Vaccines Being Tried Out

  1. Feb 9, 2018 #1

    BillTre

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    Cholera is one of the biggest killers of people. One of the Horseman of the Apocalypse (pestilence).
    It causes extreme diarrhea which can cause death from dehydration.
    It is spread through drinking water contaminated with human waste.

    Vaccines are now being tested in real non-lab situations.
    Vaccine numbers had been built up and are being used to immunize where outbreaks are occurring (the vaccines seem to more rapidly increase immunity than was initially expected) and being contemplated for use in more prophylactic situations.
     
  2. jcsd
  3. Feb 10, 2018 #2

    Baluncore

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    Vaccines against cholera have been around for over a century, oral vaccines for over two decades.

    Anything that can reduce the spread of a cholera outbreak is important. Vaccinations often work well against viruses, but not so well against bacteria where they typically prevent only about half of the expected infections.

    Medical carers cannot rely on vaccination against a bacterial threat in their workplace. Hand-washing and other hygienic practices are essential.

    There is no question that the availability of clean drinking water must be the primary aim. That will reduce the incidence of many viral and bacterial infections, including dysentery, cholera and typhoid.

    A good way to protect the population of a first world country is to always have a stock of vaccines for diseases that may be imported by airline passengers entering the country. Hopefully the stock will not be needed. Any government owned stockpile of vaccine must be replaced on a continuous basis by the pharmaceutical industry.

    The best way to protect a first world country is to circulate the stock early and donate the replaced stock through an international organisation such as the UN, to where it can be used to reduce the pool of endemic disease that threatens the first world.
     
  4. Feb 12, 2018 #3
    Personally, I would use Bacteriophages to kill bacteria as efficient killers of them that self-reproduce from the killing process of the bacteria, but barring that Baluncore is correct anything that can stop the spread of a disease is good.

    wpid-virulentphagelifecycle1335388305433.png
     

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    Last edited: Feb 12, 2018
  5. Feb 14, 2018 #4
    The problem with using phages to control disease in humans is that our own immune system rapidly clears them and the antibodies created are long lasting. As we are exposed to all sorts of phages on a continuous basis it is likely that we already have antibodies against many of them. Russia seems to have the largest repository of known bacteriophages but using them clinically has been very difficult.
    The latest oral vaccines appear to offer around 87% protection against Vibrio Cholerae, at least in the short term, stockpiling this vaccine in developed countries with effective water treatment would be pointless really, there would be little possibility of spread. The fact that the illness develops so rapidly means that it is unlikely to be imported, an outbreak would require a breakdown of sanitation and an asymptomatic carrier, which seems to be what happened in Haiti.
    http://www.thelancet.com/journals/langlo/article/PIIS2214-109X(16)30211-X/fulltext
     
  6. Feb 20, 2018 #5

    BWV

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    The childhood HiB, Pertussis, Pneumococcal and Tetanus vaccines (all bacteria) are 90%+ effective
     
  7. Feb 21, 2018 #6

    Baluncore

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    90%+ is wishful thinking, I do not believe you. Where do you get that data from ?

    Tetanus is low-cost and effective, but children need 6 shots, then as adults need a booster shot every 10 years. According to wikipedia Pertussis whole-cell vaccine is about 78% effective. Pertussis, acellular vaccine is 71–85% effective. The effectiveness of the vaccines appears to decrease by between 2 and 10% per year with a more rapid decrease with the acellular vaccines.
     
  8. Feb 22, 2018 #7

    BWV

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  9. Feb 22, 2018 #8

    Baluncore

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    You are cherry picking and only considering the multi-dose childhood DtaP data from the first year. You are ignoring the 30% of children not fully protected 4 years later. The full CDC quote, with my bold is;
    Given the population distribution in those groups I would say that less than half of the population was protected.
     
  10. Feb 22, 2018 #9

    BWV

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    Ok but your are straining at gnats, all I was doing was objecting to your blanket statement, which was posted without a reference, that vaccines against bacterial diseases "typically prevent only about half of the expected infections"
     
  11. Feb 22, 2018 #10

    BWV

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