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Why Isn't There A Readily Available Lyme Disease Vaccine?

Discussion in 'Microbiology' started by Dr.Scorpiowoman, Jun 26, 2018.

  1. Dr.Scorpiowoman

    Dr.Scorpiowoman Golden Member

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    There is no Lyme disease vaccine at present not because no one ever developed it but because GlaxoSmithKilne withdrew LYMErix™ in 2002

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    This question originally appeared on Quora.com

    Answer by Tirumalai Kamala, Immunologist, Ph.D., Mycobacteriology, on Quora:

    'Why isn't the Lyme disease vaccine readily available, especially given the projected Lyme outbreak this year?'

    The Spirochaete Borrelia burgdorferi causes Lyme disease when ticks such as Ixodes scapularis that carry it bite an unsuspecting person when they're outdoors.

    There is no Lyme disease vaccine at present not because no one ever developed it but because GlaxoSmithKilne withdrew LYMErix™ in 2002. Anti-vaccine hysteria, especially high in the wake of the fraudulent 1998 Wakefield vaccine-autism link, boosterism by media more invested in sensationalizing than in educating, exploiters sensing an opportunity for easy money, the usual suspects figure in this vaccine story. Given such a history, it's no wonder major vaccine makers have since largely chosen to stay away from this particular ball of wax.

    Emerging in the 1990s, LYMErix™ and ImuLyme™ were two Lyme vaccines that targeted the Lyme bacterium's outer surface protein A (OspA). For unknown reasons, ImuLyme™ never even made it to the market.


    LYMErix™ came to the US market in 1998 with several drawbacks, though none were deal breakers.

    • Efficacy of <80%, meaning not everyone who got the vaccine would be protected.
    • Licensed for those between 15 and 70 years of age. Not tested in children even though they are a high risk population for Lyme disease.
    • Only designed to protect against Borrelia burgdorferi strains dominant in North America, not against other international subspecies, so only useful in the US and Canada.
    • A complicated regimen, two doses a month apart first and then a third dose a year later, questions about its ability to drive long-term protection remained.
    Its withdrawal embodies the years-long erosion of US public trust in vaccines, driven in this case by (1, 2, 3, 4, 5, 6, 7).

    • A mealy-mouthed recommendation by the Advisory Committee on Immunization Practices that failed to vigorously recommend the vaccine for those at highest risk (those who lived in the Northeastern states endemic for the tick that spreads Lyme), appearing to consider it a luxury rather than a public health necessity.

      • Why would people in high-risk regions go for the shot when the ACIP recommendations meant costs wouldn't be reimbursed by insurance companies?
      • Since LYMErix™ wasn't recommended for routine administration, it wasn't covered by the Vaccine court that compensates individuals injured by vaccines and so doing, serves to partially protect vaccine makers from the burden of lawsuits.
    • The vaccine maker, choosing to market directly to the lay public rather than make the effort to educate doctors on the benefits of vaccination for a disease then and even now poorly understood by them and poorly diagnosed.
      • Education was even more essential than usual for LYMErix™, which works very differently from a traditional vaccine. Rather than kill the Lyme-causing bacterium, Borrelia burdorferi, in humans, it kills it in the ticks. When the tick feeds on a vaccinated human, it slurps up the anti-OspA antibodies, which travel into the tick's gut and eliminate the bacterium before it can travel to the tick's salivary glands from where they would be injected into the next unsuspecting human host who walked by and got bitten by that tick.
    • Relentless media coverage of so-called 'vaccine victims' where non-profits such as Lyme Disease Network and Lyme Disease Foundation generously added fuel to the fire.
    • A class action law suit by the Philadelphia law firm of Sheller, Ludwig and Bailey, representing 121 individuals who claimed they experienced serious adverse reactions (mainly joint problems) to the vaccine. When the case settled out of court, the prosecuting lawyers got >$1 million in legal fees but none of the so-called 'vaccine victims' got any financial compensation. GSK never admitted the vaccine caused harm and instead insisted its decision was based on economic considerations (cost of a lengthy lawsuit plus soft market for the vaccine). From $40 million in 1999, sales had shrunk to a mere $5 million by 2001.
    Post-marketing phase IV studies of LYMErix™ accumulated a total of >1.4 million Lyme vaccine doses by 2001 with 905 reports of mild reactions and 56 of arthritis, ironically an arthritis rate the same as that in unvaccinated individuals! Neither was there an arthritis spike after the 2nd and 3rd vaccine doses when a problem with vaccine safety would have shown a link between vaccine and arthritis. In other words, no data to substantiate ginned-up claims of Lyme vaccine safety issues.

    In the meantime, in a sign that nature usually has the last laugh, the market for a Lyme disease vaccine is anything but soft these days as the tick that spreads it, Ixodes scapularis, expands its geographic reach relentlessly year on year, courtesy of climate change, even as the CDC estimates ~300000 people in the US are diagnosed with it each year. Note the emphasis on estimate. Lyme disease lab diagnosis remains far from definitive while most doctors still remain poorly trained to clinically diagnose it so only estimates are possible. The result is that who knows how many people with Lyme disease never even find out they have it even as the tick that carries it marches on unstoppably into newer areas.


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