Monday, September 10, 2012

much ado about timing of measles shot

A newspaper snippet is making the round on the interwebz...
Timing of measles vaccine questioned Quebec had a large outbreak of measles in 2011, with more than 700 cases reported. Surprisingly, a number of the teenagers infected had received the recommended two doses of vaccine. A study De Serres did last year showed those who got their first shot at 12 months of age were three times more likely to get infected than those who got their first shot at 15 months of age; his new study put the risk at six times more likely.
We know what will become of this in the claws hands of anti-vaccine vaccine-critical folk. "An outbreak in Quebec where 700 vaccinated teens got measles proves that current vaccination schedule makes teens six times more likely to contract measles". So let's look at the actual study: It analyses measles cases in one high school in Quebec with 1306 students. The index case was a teacher, who imported the measles. This teacher had been vaccinated once. Passive and active surveillance identified 110 students with measles in the following outbreak - I'll bold the notable passage:
Of the 110 student cases identified, 98 were therefore classical (23 laboratory confirmed) and 12 were attenuated (Table 2). Attenuated cases were only found in 2-dose recipients, none of whom had been revaccinated as part of outbreak control.
So out of 1306 pupils, 110 got sick, 12 of them mildly. Mild cases had been vaccinated twice. Have a look at this handy little table:


The overall attack rate among unvaccinated students was 82%,
the overall attack rate among vaccinated students was 4.8%.

Vaccine efficiency was 95.9% for one dose of MMR. It was 95.5% against classical measles and 94.1% against any measles in the 2x vaccinated group. The authors then analysed the 2x vaccinated students to see whether vaccine protection waned with age. That was not the case. Instead they found that for students who were vaccinated at 12 months, vaccine efficiency was 93%, whereas in students who had had their first MMR, it was 97.5%. When you compared those two groups with each other, the relative risk of the 12-months-at-first-vaccination to contract measles compared to the 15 monthers was about 4.35x higher, which was borderline significant (p=0.04). That bit made the news. The fact that measles vaccination offered highly significant protection against measles somehow didn't. Well, now you know.

7 comments:

  1. “How safe is the MMR vaccine?


    “The drug company that makes the MMR vaccine publishes an extensive list of warnings, contraindications, and adverse reactions associated with this triple shot. These may be found in the vaccine package insert available from any doctor giving MMR, and in the Physician’s Desk Reference (PDR) at the library.(8,9) The following afflictions affecting nearly every body system — blood, lymphatic, digestive, cardiovascular, immune, nervous, respiratory, and sensory — have been reported following receipt of the MMR shot: encephalitis, encephalopathy, neurological disorders, seizure disorders, convulsions, learning disabilities, subacute sclerosing panencephalitis (SSPE), demyelination of the nerve sheaths, Guillain-Barre’ syndrome (paralysis), muscle incoordination, deafness, panniculitis, vasculitis, optic neuritis (including partial or total blindness), retinitis, otitis media, bronchial spasms, fever, headache, joint pain, arthritis (acute and chronic), transverse myelitis, thrombocytopenia (blood clotting disorders and spontaneous bleeding), anaphylaxis (severe allergic reactions), lymphadenopathy, leukocytosis, pneumonitis, Stevens-Johnson syndrome, erythema multiforme, urticaria, pancreatitis, parotitis, inflammatory bowel disease, Crohn’s disease, ulcerative colitis, meningitis, diabetes, autism, immune system disorders, and death (Figure 49).(10,11)”

    The most interesting fact given in the 1968 circular and something that needs a great deal of thinking about today is in Section 8 – Relation to other immunising procedures where it offers the following advice:-

    “An interval of three to four weeks should normally be allowed to elapse between the administration of measles vaccine and any other vaccine, whichever is given first.”

    My question is, if this is so, then why the hell did they dream up putting the measles vaccine into a multi vaccine just a few years later? It is obvious to me that their very clear advice seems to have gone completely out the window, as nowadays, not only is the measles vaccine part of a multi vaccine but now they are saying it is safe to give children many vaccines in one day. In fact Paul Offit is actively giving the advice to parents that multiple vaccines are quite safe saying that even as many as 100,000 are perfectly safe. I wonder how he would feel offering to be the pin cushion he wants our children to be.

    “Paul Offit, M.D., chief of infectious diseases at the Children’s Hospital of Philadelphia and the Henle Professor of Immunologic and Infectious Diseases at the University of Pennsylvania School of Medicine, is the Chief US spokesman/liar for vaccination. The Voice of Sauron. On the board of Every Child By Two. Believes children can safely take 100,000 vaccines!”

    Mind you in saying this according to some he does share the patent on the Rotavirus vaccine Rotateq, that looks to have made him millions. Honestly what some people will do to get rich is beyond me.

    http://vactruth.com/2010/05/20/government-papers-on-measles-vaccines-exposed/


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    1. Have you actually read this http://www.pdr.net/drugpages/productlabeling.aspx?mpcode=52402160 ? What some people will do indeed.

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  2. Dear Brave Anonymous: As you have labeled anyone who questions vaccines as uninformed or misinformed, don't understand probability or statistics, have conspiratorial thinking, or get information from brain dead websites, it is no surprise.

    Actually, it is not much a label, but more of a description of everything you have posted, including the cut and paste diatribes. Though, at least now you have included quotation marks and attribution.

    Nothing you posted shows the MMR vaccine carries more risk than measles. Nor anything that shows it is cheaper to let every kid in this country get measles. That would be several million cases per year, with hundreds of thousand ending up in the hospital, thousands becoming permanently disabled and hundreds of deaths. And that is just going on the figures from the 1950s, when the USA population was half of what it is today.

    You still have not yet figured out that we much prefer links to the original peer reviewed literature, and not links to "therefusers" and "vactruth". Your sources are often desribed: as skewing science, shifting hypotheses, censoring dissent, and attacking critics; also discussed are frequently made claims such as not being "anti-vaccine" but "pro-safe vaccines", that vaccines are toxic or unnatural, and more. Recognizing disingenuous claims made by the anti-vaccination movement is essential in order to critically evaluate the information and misinformation encountered online.



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  3. How about referring to the current Merck MMR Vaccine Prescribing Information...not the 1968 version that you refer to, Anonymous?

    http://www.merck.com/product/usa/pi_circulars/m/mmr_ii/mmr_ii_pi.pdf

    Those conditions that you say have been "reported"... are just that. The FDA regulations stipulate that all "Manufacturers Prescribing Information Sheets" for vaccines, other biologicals and all medicine, licensed for use in the USA, must contain any and all conditions that have been "reported"...even those that have NOT BEEN verified as associated with the use of the prescribed product.

    Show us where those "reported" conditions, have been investigated thoroughly and been reported (not by Vactruth), by researchers and been confirmed as associated with the administration of MMR vaccine. Try PubMed and look for published articles from the NEJM, JAMA and Pediatrics journals.

    Here another of your inane remarks...

    "The most interesting fact given in the 1968 circular and something that needs a great deal of thinking about today is in Section 8 – Relation to other immunising procedures where it offers the following advice:-

    “An interval of three to four weeks should normally be allowed to elapse between the administration of measles vaccine and any other vaccine, whichever is given first.”

    Then, this "other" opinion from you...

    "My question is, if this is so, then why the hell did they dream up putting the measles vaccine into a multi vaccine just a few years later? It is obvious to me that their very clear advice seems to have gone completely out the window, as nowadays, not only is the measles vaccine part of a multi vaccine but now they are saying it is safe to give children many vaccines in one day....."

    Try to muck your way through the CDC Pink Book, especially this chapter for proper "spacing" of vaccines, especially the spacing of live vaccines that are not given simultaneously, Anonymous:

    http://www.cdc.gov/vaccines/pubs/pinkbook/genrec.html

    You really are gullible or a fool to think that Vactruth provides reliable information. And, you are beyond ignorant to not know about the minimal intervals to administer live vaccines, not given simultaneously.

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  4. Catherina,

    Thanks so much for posting this and pointing out the bits of the study that weren't reported. No surprise, really, since the bit that was is so much more newsworthy than, "Hey, look! Unvaccinated kids were waaay more likely to get sick. Who knew?"

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  5. Anon - your first comment was spam, it is in the spam folder, where it belongs. This site is not a "dump your vaccine conspiracy here" tip.

    Lilady has nailed it: why do you cite something from 1968? Oh, you just copied and pasted it from a page that catered to your agenda. That makes sense then, I guess.

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