What if you could prevent autism?

21 Sep

What if you could prevent autism?  What if there were a way that people could dramatically reduce the number of people born with autism? What if it took a concerted effort on the part of everyone to make it happen?  Should we do it?  Would people complain?

Would we respect the lessons of  the past if it had already happened?

Well, it may have already happened.  “May” as in it requires correlating one set of trends with California DDS numbers on Autism.  We all know how dangerous that can be.  CDDS data are not epidemological.  They don’t tell you how many people in California have autism, they tell you how many people in California are getting services under autism.  People who forgot the importance of that distinction have found themselves promoting an epidemic that didn’t happen. 

With that lesson in mind, let’s look at some CDDS data.  Let’s look at the number of clients with autism by birth year.  Further, let’s look at these data as they looked in 1986.  That is pre “epidemic”.  Pre DSM-IV.  That is before schools added autism as a separate category. 

  CDDS autism clients by birth year as recorded in 1986The data show something I didn’t expect: a drop in the number of autism clients.  Not just the noise that gets those promoting the epidemic to say, “look from one quarter to the next we see a drop”.  Nope, this looks like it could be the real deal, that elusive goal of those claiming an epidemic.  It happened in the 1970’s. 

Keep in mind that these data are from 1986.  So the drop in numbers in the 1980’s is because those people hadn’t been identified yet.  It isn’t “real”.

Also, keep in mind that these are raw numbers.  No attempt to normalize into a rate (individuals with autism per 1,000, say) has been made.  California went through a notable population increase over this time.  So, any drop in rate estimated (from these non-epidemological data) would be even greater.

Given this great amount of limitations, take a look at this graph.  These are the autism clients by birth year as reported in 1986.  The data are noisy, but I see a big plateau for kids born in the 1960s with about 100 clients per birth year followed by a second plateau in the 1970’s at about 75 clients per birth year.

That is an indication that there may have been  a roughly 25% drop from one decade to the next in the number of people with autism.   What happened?

Rubella prevalence in the USWell, since I recently posted about the dangers of only digging deep enough to support your own pet theory (and that is good advice), I’ll put this forward as a “Medical Hypothesis”.  Consider this: the Rubella vaccine was licensed in the U.S.  in 1969.  What happened before that?  There was a Rubella epidemic in the 60’s.  Lot’s of kids were born with CRS, Congentital Rubella Syndrome: a known cause of autism.

What if the Rubella vaccine is reducing the number of kids born with autism?  Wouldn’t that be a good thing that should catch the attention of the “autism community”?  It is a little strange that one would have to use this route. Keeping Rubella at bay results in a lot fewer deaths, including the unborn.  Also, fewer would become deaf, fewer would have congenital heart defects.

From the CDC:

The greatest danger from rubella is to unborn babies. If a woman gets rubella in the early months of her pregnancy, there is an 80% chance that her baby will be born deaf or blind, with a damaged heart or small brain, or mentally retarded. This is called Congenital Rubella Syndrome, or CRS. Miscarriages are also common among women who get rubella while they are pregnant.

I would have thought that would be enough to get the point across: Rubella is something to prevent.  Perhaps the vaccine is a good thing?  Perhaps it is working?  I don’t think there is any “perhaphs” about it.  Overall, preventing Rubella is a great thing.  But some people seem to want to deny that vaccines even work.

Take a very rough estimate.  Assume from these data that 25 people a year in California alone have had autism prevented by the Rubella vaccine.  From 1970 to 2007, that works out to 675 people.  And that is just a secondary benefit.

Maybe by calling the Rubella vaccine “preventing autism” it will catch the eye of those who have somehow forgotton how bad this disease is.

13 Responses to “What if you could prevent autism?”

  1. Ms. Clark September 22, 2007 at 00:05 #

    Thanks, Sullivan. This is fascinating.

    When Wakefield scared people off the MMR rates of autism climbed…. we have thought that Andy Wakefield stories caused autism… 🙂

  2. Joseph September 22, 2007 at 01:45 #

    I think you’re on to something there. That drop from the 60s to the 70s doesn’t look like the result of a random fluctuation. And I doubt awareness went away all of the sudden in the 70s.

  3. Schwartz September 22, 2007 at 15:18 #

    Is there any theory as to why rubella induced Autism would have such a lopsided effect on boys vs girls?

  4. Ms. Clark September 22, 2007 at 18:34 #

    Schwartz, who said rubella induced autism has a differential effect on boys and girls? It might, but I’ve never heard that before.

  5. Sullivan September 22, 2007 at 23:26 #

    I haven’t found a gender breakdown of CRS or CRS induced autism. One of the papers on the 1960’s epidemic (by Chess) is on neurodiversity.com, but I don’t see it there.

  6. Schwartz September 23, 2007 at 01:21 #

    First, I want to state my position up front so that I don’t get flamed for being irresponsible. I think that one case of CRS in children is one too many.

    Second, I think that Rubella vaccine (MMR or monvalent if prefered) should be given at an appropriate age (and I don’t think under 2 years old is appropriate).

    I also think that given the amount of genetic screening that occurs these days, it should be very simple to screen women who want to consider pregnancy for natural or vaccine induced immunity — vaccines are no guarantee of immunity, although, fetus’ can apparently still get the disease even if the mother is immune (most of the time it is likely from older medical staff, not children).

    If we want to validate your theory and CRS was to blame for any significant percentage of known Autism cases in the past or in the present, and we know that Autism is far more prevalent in boys vs girls, it stands to reason that Rubella induced Autism would have to maintain a similar ratio. I’ve never seen a hypothesis that shows any bias of CRS toward boys or girls.

    There are a few other problems as well. As I understand it, before vaccination, rubella outbreaks occurred every 6-9 years (CDC’s “Epidemiology and Prevention of Vaccine-Preventable Diseases,” 5th Edition (1999)), with the last being in 1964-1965. Since you don’t have the CRS data for that time period, we can’t confirm this, but I would have expected to CDDS data to show a cyclical pattern if indeed CRS was a significant contributer to Autism cases before vaccination.

    One other item that you haven’t addressed is the percentage of CDS cases that actually become Autistic. From the data I’ve read (CDC vaccine page) only 1800 / 20000 CRS cases had complications of “mentally retarted” and they make no mention of Autism at all.

    I may be slow, but I couldn’t figure out how you get the rough estimate of 25 Autism cases per year from rubella/crs?

  7. Matt September 23, 2007 at 01:37 #

    Take a look at the CDDS Data (again with all the caution noted).
    Here is the report from 2002.

    Click to access Dec02_Quarterly.pdf


    I chose this for a reason. The 42-51 year age group is essentiall those born in the 1960’s. Similarly, you can correlate other age groups with other decades.
    Take a look at Mental Retardation–not autism.
    Page 42–Profound MR
    ages 32-41: 2,469 clients
    ages 42-51: 2,826
    ages 52-61: 1,351
    A fair peak for the ages 42-51 group.
    This is *not* seen for other MR groups.
    Severe:
    ages 32-41: 2,794 clients
    ages 42-51: 2,777
    ages 52-61: 1,251
    Moderate:
    ages 32-41: 5,342 clients
    ages 42-51: 4,116
    ages 52-61: 1,993
    For the other mental retardation categories, it gets even farther from a peak.
    Similarly, not evidence, but a suggestion. It looks like CRS could have caused an increase in not only mental retardation, but in those with the greatest challenges.
    If so, it looks like a really good thing to avoid.
    Matt

  8. Schwartz September 23, 2007 at 02:34 #

    That data is interesting. The other cases of MR may not peak in the birth year of 65 but a bit later. That actually correlates with the (unfortunately cutoff) graph above where the CRS cases seem highest circa 1970.

    But neither graph really correlates the actual outbreak from 1964-1965.

  9. Ms. Clark September 23, 2007 at 07:36 #

    There might be a reason to preferentially enroll males or females in the DDS of kids born in the 1960’s. If a girl was born in 1964 with CRS, her mother would have been born around 1940 maybe 1930. Mothers then that might have been more inclined to keep a girl at home than a boy, if the main DDS services for adults in that age range was day programs and group home living arrangements.

    But yeah, it seems like there would be more girls proportionally among the 1960’s born ASD people in the CDDS, if the extra 25% of autistics born in the 1960’s were there because of rubella (over the background rate which would be closer to what was in the 1960s.)

    One would suppose that the CDDS could give the break down of gender for those years.

    The older autistics (say the were ones made autistic by rubella) in the 1950’s and before, it seems that they would be less likely to be enrolled in the DDS. The DDS wasn’t established until 1969. I never heard of the DDS growing up here in California, so it’s not like everyone knew about it. A lot of the autistics would have been shipped off to state hospitals (some of them would have been shifted to group homes in the 1970’s) a lot of them died in state hospitals, and many parents just considered their disabled kids to be their responsibility and didn’t think in terms of entitlements and what the gov’t owed them.

    I know a man whose brother entered the DDS system at age 60 something. He had lived with his parents (they were elderly) and so at age 60 he went to live in a group home and was enrolled in the CDDS for the first time.

  10. Sullivan September 24, 2007 at 04:00 #

    “I also think that given the amount of genetic screening that…”

    I am not following how genetic testing will help here. A “titer” is more a more useful test in determining if there is immunity. Now, for a young child, I also don’t see how “natural” immunity will be present unknown to the parants. It would involve an infection, and Rubella doesn’t seem to be a very stealthy disease.

    “I’ve never seen a hypothesis that shows any bias of CRS toward boys or girls.”

    First, you would want data, not a hypothesis. Second, I don’t see why Rubella induced autism would need to follow the 4:1 ratio common with autism overall. It would seem likely, but it may not be the case. If not, it would be an interesting and potentially useful path to work on for research.

    As to whether the data should show some oscillations with outbreaks–yes. However, these will be modified by at least three factors: the intensity of the epidemic; the California population; and the identification rate. We don’t know the intensity, as you have noted. We know that the California population has been undergone a very large growth over the time period of interest. The data in the graph are not normalized into a rate by dividing by population. Lastly, the identification rate is somewhat of a debate. However, I would contend that the identification rate for older clients is lower.

    The Chess paper on Neurodiversity.com discusses the fraction that became autistic by the standards of the time. It is low–about 5% if I recall correctly. That would mean about 500 cases total of CRS per year in California to account for 25 autism cases per year, as estimated. Given 20,000 reported nationwide in the epidemic, this seems not unreasonable.

    As to the estimate of 25/year–check the top graph. It shows that the number of autism clients dropped from about 100/year in the 1960’s to 75/year. That is where that estimate came from.

  11. Schwartz September 24, 2007 at 21:17 #

    Sullivan,

    I should have been more clear in my sentence about genetic testing. I meant to point out that we spend a lot of money on genetic tests (some of which provide a lot of false results) for pregnant women, that it shouldn’t be a big stretch to add a test for immune status to diseases that present a danger during pregnancy, like rubella.

    Even vaccination does not prevent 100% of the diseases and Rubella’s symptoms are very common in children, so you wouldn’t really know if they got it. There are many childhood illnesses (virus’ in particular) that cause low grade fever and rash.

    You are right that data is better than a hypothesis, but you typically need both to be confident of your observations and conclusions. I also looked for data and wasn’t able to find any discussion of bias between boys/girls begin affected.

  12. Wanda Buffington September 26, 2007 at 04:52 #

    Hi Jenny,
    I saw the Opera Show, when you were on talking about your son. When you said that there was a specific time frame that children like yours have in which they can learn tools that they can use for the rest of their lives, I thought of my studies in linguistics at UCLA. For some reason it made me think about the “language faculty” that is present in children’s minds that allows them to learn a language. This “language faculty” disappears after the age of around 13 year of age. If a child does not learn a language of some kind during that period, they can never learn to talk as far as getting the words in the right order. It was thought prior to a study at UCLA that children learn to speak from their mothers by mimicking them. This was wrong because when they found this child after the age of 13 who had never learned to speak, she could not learn by repetition how to get the words in the right order. They worked with her for 8 years, but she could not get the words in the right order or right tense. Maybe this time frame that you spoke about with children like your son has to do with this language faculty in some other way of communicating. I know it is the same with hearing impaired or deaf children. If they do not learn a language of some kind, for instance, American Sign Language, they will never be able to speak if they get their hearing back later. Maybe this is another avenue to investigate as far as this time frame you were speaking of, maybe there is a connection.

    I hope this make some since. Ask around about this “language faculty” which goes away after children don’t need it anymore. That is why it is easier for children to learn additional languages easier than adults.

    Good Luck
    Wanda Buffington
    UCLA Alumni 2004

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  1. Autism Blog » Epidemic or greater awareness? : » Autism news and opinion - October 4, 2007

    […] autism clients as listed in 1986 and 2007 by birth year. The 1986 (in black) data are the same as shown before. The drop in the client count in the early 1980’s is an artifact: those kids weren’t […]

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