Monday, August 29, 2016

Measles Math

The initial article concerning itself with SB277.  In essence, special snowflakes were shown the door.

What follows is a discussion had with a AVer. Use AV tropes, I will call you a anti-vaxxer.
Vaccines don't work
  • "a strain of measles that isn't covered in our USA MMR vaccines." 
Disingenuous math (measles will infect and cause disease in about 90% of those who are exposed and who have never been infected or immunized previously).
  • "It not only wasn't unvaccinated American kids who started this outbreak, but no American kids (or adults) who were fully up-to-date on their measles vaccines would've been protected from this outbreak anyway." 
The ole sanitation saved us trope,,,
  • "Our best weapons against disease are being well nourished, having access to clean water, good sanitation, good hygiene, and sick people staying home, out of the general population."

My initial response ended up being two pages.  Much too long for a post response on FB.  So here it be,,,

So you have no support for your statement ",,,no American kids (or adults) who were fully up-to-date on their measles vaccines would've been protected from this outbreak anyway." Or "B3 (genotype) is not covered by MMR".  Good to know. 

While it is true that vaccines are not 100% fool proof, ie. some people do fall through the crack of vaccine coverage even with the shot, it is the best weapon we have in fighting this potentially deadly disease.  (A well known issue and why herd immunity is so vital in protecting those that don't take to the vaccine or can't take the vaccine for medical reasons.)

The insinuation that sanitation and hygiene where lacking pre-1970 is a bit insulting and quite confusing as many individuals lobby for the "good ole days".  My father remembers quite well taking a bath and flushing a toilet during the 30s,40s, and 50s etc.  He has no recollection of shitting or dumping a bucket of piss in the streets.

Not sure what the gobbledygook about the genotypes was supposed to accomplish other than sounding scary.  Would have been nice if you explained that a genotype is used to identify were (locale) a particular strain of virus is from.  Genotyping has an "important role in tracking transmission pathways during outbreak investigations. Genotyping results can help confirm, disprove, or detect connections among cases. If two cases have matching genotypes, they may be connected even if the connection is not obvious,,, can help establish which foreign country may be the source of an imported U.S. case, since different genotypes circulate in different countries."

Your use of numbers is quite impressive as well, to bad it is (as Orac so aptly states it), a "mathematically ignorant line of argument because it neglects how small the number of unvaccinated children usually are relative to the vaccinated. Raw numbers mean little. What really needs to be examined is the relative risk of infection of the unvaccinated compared to the vaccinated during an outbreak, and, depending on how effective the vaccine is, that relative risk is usually rather high."

So you asked, "Digging a bit deeper I see references that suggest that since there's only 1 serotype, any measles vaccine will protect against all genotypes. What I don't see is data to back that up. If you see it let me know, b/c I'd like to take a look."

Regretfully I am not privy to the information used by science to determine that the multiple genotypes are susceptible to the single vaccine used.  (Sadly my googlefoo has failed!!)  But what I do have is a statement by the CDC stating as such, "Measles is caused by a single-stranded, enveloped RNA virus with 1 serotype. It is classified as a member of the genus Morbillivirus in the Paramyxoviridae family. Humans are the only natural hosts of measles virus."

Why on god's green earth would I contest the scientific consensus of the last 50+ years when it is known,
The virus can vary a bit genetically, but they all “look” the same when it comes to our immune systems. When a virus is all of the same serotype, they have the same antigens (proteins that our bodies recognize and make an immune response to) on the outside.

It shouldn’t matter of what genotype the measles virus is (and they do vary), they all will be recognized by a vaccinated body’s immune system in the same way.

If you’re vaccinated, your body WILL recognize any strain/genetic variant of measles. And we confirm that with how very effective our measles vaccine is.
I have accepted the science.  I have accepted that individuals smarter than I have determined the "what fors" behind the serotype and genotypes. So unless you want to disregard the CDC and the science behind them, I will have to take their word.

That takes me back to the initial graph, we can see how effective the vaccine has been,
In the decade before the live measles vaccine was licensed in 1963, an average of 549,000 measles cases and 495 measles deaths were reported annually in the United States. However, it is likely that, on average, 3 to 4 million people were infected with measles annually; most cases were not reported. Of the reported cases, approximately 48,000 people were hospitalized from measles and 1,000 people developed chronic disability from acute encephalitis caused by measles annually.
Since 2000, when measles was declared eliminated from the U.S., the annual number of cases has ranged from a low of 37 in 2004 to a high of 667 in 2014. The majority of cases have been among people who are not vaccinated against measles. Measles cases in the United States occur as a result of importations by people who were infected while in other countries and from transmission that may occur from those importations. Measles is more likely to spread and cause outbreaks in U.S. communities where groups of people are unvaccinated.
What I do have is this explanation, which is much too long to copy-pasta in its entirety, but I will leave you with the conclusion,
In the end, all of the available evidence shows that the antibodies produced against one genotype of measles protect against all of the other genotypes, as well. Even though the vaccine only contains genotype A, the antibodies you produce as a result of being immunized will protect you from infection by, for example, the B3 genotype in the California measles outbreak. Although anti-vaccine activists are now claiming that the vaccine doesn't work because the genotype in the vaccine is different than the wild virus in the outbreak, the evidence shows that they are wrong. Rather than accepting their errors and admitting their mistake, they invent new explanation to defend their ideology. Their claim is simply another in a long line of failed rationalizations to support their belief that vaccines are bad. It's nothing more than cognitive dissonance on display.

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