Felix Salmon

The most dangerous school in Los Altos

By Felix Salmon
November 1, 2011

A week or so ago, Matt Richtel wrote a long and glowing profile of the Waldorf School of the Peninsula, looking into the apparent irony that a Silicon Valley school is decidedly low-tech; he quoted one parent, Alan Eagle, a senior Google employee, as saying that “I fundamentally reject the notion you need technology aids in grammar school”.

But there’s more to technological progress than iPads. And I wonder what Alan Eagle would say if he knew that fear of life-saving technology at the Waldorf School is exposing his children to a much-heightened risk of painful, untimely, and easily-preventable death.

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The first thing to say about this tragic chart is that both Los Altos city and Santa Clara county have extremely low immunization rates. The right level of immunization is 100%, and rates of 90% or 94% are very dangerous indeed.

But 23% is positively evil.

This is a very dangerous level of immunization–the level where herd immunity gets lost, disease reservoirs are established, and children emerge from their school to infect infants, immunocompromised adults, and people whose vaccinations didn’t take or have waned, with potentially fatal diseases.

No responsible parent would ever let their child attend a school with a 23% immunization rate. And indeed there’s a strong case to be made that public-health officials should simply refuse to allow any such school to open its doors unless and until that rate improves. I’ll be charitable here and assume that Richtel didn’t know this number when he wrote his piece — but still, the NYT owes its readers something of an apology here for leading them to believe that there might be something admirable about this sinkhole of highly-dangerous fear and ignorance.

By far the best book on this phenomenon is The Panic Virus, by Seth Mnookin; I can highly recommend it. He tells of how when public-health officials try to work out which areas are at highest risk of fatal outbreaks, one thing they do is look at a map of Whole Food stores — it’s the crunchy-granola college-educated liberals who are by far the worst offenders when it comes to putting their own children and everybody else’s at risk. And they love to eat up pseudoscientific claptrap about “immature thymus glands” when it’s published by outlets like the Huffington Post.

It’s a statistical certainty that children die, unnecessarily, when immunization rates fall. The Los Altos parents sending their kids to the Waldorf School of the Peninsula are at best misguided and at worst downright malign. No matter how skeptical they are of technology, school administrators have an overriding moral duty to do something about this. Now.

Update: I should have put this in the original post, sorry, but the chart comes from the Bay Citizen’s immunization pages, which show that “at Waldorf School Of The Peninsula, 72.73 % of kindergartners weren’t fully immunized in the 2010-11 school year due to their parents’ personal beliefs”. The data comes from the California Department of Health.

Update 2: A fascinating comments thread, which is worth reading, or at least skimming through. Thanks in particular to LaraR, who notes that kids can’t enroll in public schools in Santa Clara unless they’re immunized. Which seems to have had the unintended consequence that parents who don’t want to immunize their kids all end up sending their kids to the Waldorf School, with potentially disastrous consequences. There’s already a pertussis epidemic in the county.

52 comments so far | RSS Comments RSS

Felix, do you have evidence for the strong claims you are making? (Megan McArdle didn’t cite any.) When you start talking about “herd immunity”, “disease reservoirs”, and the dangers of attending a school with a low immunization rate, I suspect you are misapplying data derived from community-level research.

A country with a 23% immunization rate would be wide open to a host of dangerous diseases that once were commonplace (and could be again). A state with a 23% immunization rate could sustain endemic disease, serving as a “disease reservoir” for the rest of the country.

But a school community of a couple hundred children?!? Yes, it would serve admirably as a rapid-spread vector if any of the children were to become infected. But a community that small cannot sustain the broader dangers that are being suggested.

I don’t disagree with the conclusion. A high immunization rate is important to society, and saves thousands of lives annually. But let’s try to keep our words grounded in fact?

Posted by TFF | Report as abusive

I guess it stands to reason that a chart from Megan McCardle would leave a lot of questions, and my question is: 23% by what metric? Only 23% of children are vaccinated at all, or only 23% of children have all vaccines?

Okay, I agree that either of those metrics is disturbing — two of my children were particularly vulnerable to respiratory distress as infants and at higher risk of serious complications if exposed to what used to be the “normal” diseases of childhood. I am not quibbling with your overall point, but the chart leaves out the kind of relevant details that ought to be of interest to those devoted to the science of epidemiology and public health.

And by the way, 100% of vaccination can NEVER be attained because some children should NEVER be vaccinated — they are immunocompromised and cannot really form antibodies and so would never benefit themselves or anyone else, and could very definitely be harmed by exposure to the vaccine (depending on the vaccine).

Indeed, they are the primary reasons why (and the primary beneficiaries when) other kids get vaccinated.

Posted by rb6 | Report as abusive

They’re not just putting their own children at risk, but their entire community as well. The risk to the rest of us is too large to let individuals choose to vaccinate or not vaccinate, because vaccines don’t always take.

Which means the risk of contracting a deadly disease is actually lower if you’ve never had a single vaccination but live in a place with extremely high vaccination rates than it is if you personally get every vaccination but choose to live in a place with low vaccination rates.

Posted by Sprizouse | Report as abusive

rb6 makes the correct point about why 100% vaccination is unattainable but apart from that your post nails it, Salmon.

What was that I read about Steve Jobs recently? That he put off surgery for the first 9 months after the diagnosis because he thought he could cure his cancer with thought, herbs and colonic irrigations? Ah yeah….Palo Alto…

Posted by ottorock | Report as abusive

Herd immunity starts to erode when childhood vaccination levels drop below 80%. However, even a few hundred kids in a single school with significantly lower vaccination rates can become the vector of a significant epidemic, because school settings are public health nightmares. I mean, spend even a day in an elementary school setting and you will know why. In any event, once the disease starts and spreads it can theoretically spread to anyone who has never been vaccinated, or whose immunity has subsided. In a state like California, that is actually a lot of people, maybe even a majority in some communities: many immigrant adults were not vaccinated as children and aren’t required to be vaccinated as adults. So posit a Waldorf family with an adult, immigrant nanny who is exposed to measles and then in turn exposes her family, inlcuding unvaccinated infants.

Many adults born before 1962 in the U.S. were also never vaccinated for mumps, measles or rubella (MMR) (many were as well — there was a gradual escalation in percentages being vaccinated).

It would be interesting to know is how the Waldorf school compares to other private schools.

Posted by rb6 | Report as abusive

Felix, I’ll echo TFF and rb6 and reserve some judgment till the bar chart has been satisfactorily sourced. My gut may be out of touch, but it tells me that the 23% figure is an urban myth in the making.

As well, I wouldn’t call out Matt Richtel or the NYT for missing this story. As I recall, Matt’s piece wasn’t a paean to the Waldorf School, it was an exploration of the ostensible anomaly of digital professionals’ sending their children to an un-digital school. End of story?

Posted by Komanoff | Report as abusive

“However, even a few hundred kids in a single school with significantly lower vaccination rates can become the vector of a significant epidemic, because school settings are public health nightmares.”

Agreed, rb6. A setting like this is a way to rapidly turn a single case into dozens or hundreds (spotted throughout the area). I do wish the blog articles had focused more on this aspect of epidemiology.

Posted by TFF | Report as abusive

Many vaccines effectiveness wears off over time, such as varicella, and MMR. So instead of just thinking about children getting those diseases, it is also likely that an adult in the home could get sick and suffer the worst consequences.

Posted by hekatesgal | Report as abusive

How many children attending this Waldorf school have died of vaccine-preventable diseases since the school opened vs how many have matriculated from the school?

My guess: zero.

I think someone’s risk meter needs recalibrating.

Posted by cycle | Report as abusive

Lemme guess, cycle. Nobody’s died from global warming so that doesn’t exist either. I mean…look at all that snow!

Posted by ottorock | Report as abusive

Well otto, this is America. You’ll have to get used to people having abortions even in states where the majority opposes them, and you’ll have to swallow the miniscule risk of a vaccine-preventable disease related death vs interfering with someone’s civil rights and legally mandating vaccinations.

Posted by cycle | Report as abusive

cycle, the truth is, whether or not one of the kids died is just the beginning of the story. In fact, it takes a fair amount of effort to track who is ground zero of an epidemic — I had a secretary who was among those born before MMR vaccines were common and who had never been pregnant (time at which many of the unvaccinated as children get vaccinated as adults) who got measles as an adult. No one ever figure out how she contracted it. It wasn’t from the office. It could have been from a cashier at a grocery store, or any number of other places. She was seriously ill for quite a while. I was pregnant at the time and called my doctor in a panic, and that’s when I learned that doctors always check antibodies for certain diseases in pregnant women and vaccinate them if their antibodies are weak or non-existent.

It’s really hard to imagine what the world used to be like. My mother told me that when it became known that someone in a school had certain diseases, a lot of people just kept their kids at home. The mother of a friend of mine told me that she had to quit work as a teacher because of an outbreak of measles when she was pregnant. If there is no current epidemic it’s not because Waldorf kids haven’t infected people — it’s because other parents adhere to a wider understanding of what the social compact requires of them.

Posted by rb6 | Report as abusive

Right, and I think most people will continue to have their children vaccinated.

What I’m getting at is that sometimes, in a free society, you have to accept a minority doing something you don’t approve of for what you think are very good reasons. When you start violating everyone’s civil rights to attenuate a risk which is measured with several negative magnitudes, ie 10(-6) you’re on the way to Singapore.

> 100,000 alcohol-misuse related deaths per year just in the US. I got an idea, let’s make alcohol illegal, it almost worked last time. We just needed more police powers.

Posted by cycle | Report as abusive

cycle, no dispute with your general point — what is disturbing is that this particular non-conformist behavior reflects such a high level of disinformation and magical thinking by people who otherwise pride themselves on being well-educated, pragmatic, etc., and, of course, the fact that this decision (a) is potentially dangerous to people who have no idea they are at risk and (b) the degree of free riding that is assumed to be the birthright of a certain type of parent with respect to their children, who, apparently, are considered more precious than others.

But I’ll get off my soapbox. This is just the confluence of two things I hate more than just about anything else – free riding and willful ignorance. Combining them together in a single package without regard to the attendant harm to others just drives me bonkers.

Posted by rb6 | Report as abusive

cycle, you have to accept that sometimes, in a free society, people will be highly critical of your selfish choices even when you are not breaking the law. That saw cuts both ways…

And if vaccinations stopped, you could easily end up with >100,000 deaths per year from preventable diseases.

Posted by TFF | Report as abusive

cycle, we have laws against DUI. You can feel free to not vaccinate your child, but you shouldn’t be able to put other children/immuno-compromised people at risk by your own behavior. So, home school the brats all you want, Ms. Rand.

Posted by Ninguna | Report as abusive

Cycle’s point about the 100,000 deaths as a result of alcohol abuse is an excellent one, but not in the way he thinks. There are strict laws about when one’s use of alcohol becomes a danger to others. You can drink, but if you drive drunk and put others in danger you go to jail. Refusing to vaccinate places others at risk in the same way that operating heavy machinery while under the influence does. “Maybe nothing bad will happen” is not an acceptable excuse when the risks are known.

Refusing vaccinations because of belief in an urban myth falls outside of the social bargain that must be made when living in a dense urban environment. Cloaking those refusals in the constitution will only get you so far. Public health concerns are one of the areas of case law where the individuals rights are subservient to the rights of the group.

Posted by k9quaint | Report as abusive

The Waldorf schools are a cult, so nobody should be surprised by anything they do. The origination of their policies is no different than that of many religions – where the founder goes off into the mountains or the desert or wherever and comes back with a set of arbitrary proclamations on what is right and wrong.

If you start with what you want to believe, and work backwards, you can always come up with a rationalization for it. Enter the Waldorf schools. Fortunately, their high cost will protect most of the population from exposure to their fairy tales.

Posted by KenG_CA | Report as abusive

what k9quaint said

Posted by ottorock | Report as abusive

But Ken_G, if they are expensive they must be good! Right?

Posted by TFF | Report as abusive

TFF, I’m laughing. Thanks.

I’m still laughing.

Posted by KenG_CA | Report as abusive

Thanks for the warning, Felix. As a result of this sort of anti-vaccine propaganda, Santa Clara County already has a huge pertussis epidemic. At least the public schools are safer – kids can’t enroll unless they’re immunized. Too bad that among these supposedly well educated people the whole idea of public health is a foreign notion. Sheesh, meningitis and polio will be making a comeback soon if they prevail.

Posted by LaraR | Report as abusive

maybe if they quarantined them they might feel different. after all, they are a threat to others.

Posted by willid3 | Report as abusive

“Survival of the fittest.” Sometimes, fitness is measured by common sense. Let natural selection scrub the gene pool of free riders and magical thinkers. It’s happened lots of times before. Viruses don’t care if you shop at Whole Foods.

Posted by EpicureanDeal | Report as abusive

The 23% statistic is taken from the 2010 Immunization Status of Kindergarten Students from the California Department of Public Health:

http://www.cdph.ca.gov/programs/immunize  /Documents/2010IZRateTable.pdf

Posted by clr76 | Report as abusive

k9quaint – I’m sorry I was not clear. What I was trying to express was that the attributable risk of dying of a vaccine-preventable disease for a Vaccinated child living in a community with some small % Unvaccinated children is probably 1/1,000,000,000 or less. Even if I am overestimating by two orders of magnitude it is still a trivial risk. Epidemiologists very welcome to correct this.

Even if someone came out with a study showing a measurable estimate of the risk ratio whose error does not span zero, in practical terms, in real life numbers, the risk is probably – well – close to zero.

I’m not sure what to call this, except “copy that sells.”

- Insulting, devaluing and deriding a whole community of people who are part of an international educational movement that has been educating children successfully for a hundred years or so –

just to warn the rest of the world of the fearsome risk of dangerous, unvaccinated Waldorf children spreading death and disease when that risk is close to zero.

Posted by cycle | Report as abusive

Cycle: First of all, I presume you are not an epidemiologist. Please do not put forth statistics for which you have no data, no citation, and no training with with to make your own determination. 1 in a billion? It certainly would be convenient to your argument if that was the case, but you really just pulled that number out of thin air. The CDPH reports there were 461 cases of whooping cough in Santa Clara county (where the waldorf school is) for 2010 alone. For the state, there was an average of 10 cases per 100,000 and 9 deaths (8 of which were infants). Marin county had a ratio of 128 per 100,000 (12 times as high as the average) and it also had one of the lowest rates of vaccination. Contagions spread exponentially, you cannot judge them assuming linear progressions.

There are three major risks associated with contracting the major childhood illnesses (mumps, rubella, pertussis, etc). Firstly, you could die from it. Second, you could be seriously damaged by them (blindness, sterile, deafness, etc). Thirdly, you could infect someone else with the disease. Take Pertussis for instance, it is highly infectious and very dangerous to infants. Vaccinations are effective against it, but they wear off after a while and they do not always confer protection even when taken. It is unlikely that *you* will die from it, but while you have it you could expose hundreds of people to it. The idea is to take the vectors of transmission away to protect infants who have not been vaccinated yet, people with compromised immune systems (elderly, cancer patients, etc), and those for whom the vaccine did not “take”.

This isn’t rocket science. Vaccination is on the order of a “wash your hands before performing surgery” type of precaution. The only reason we are even talking about is because some guy in Britain applied for a patent on making vaccines without mercury and then made up a story about vaccines with mercury causing Autism. He tried to sell the patent and cash out, but the story blew up on him too fast. That guy is now in jail for fraud. Jenny McCarthy is not someone you should take medical advice from (even on breast implants).

Posted by k9quaint | Report as abusive

Vaccine injuries are real; watch this recently released movie (free this week) for a few examples: http://vimeo.com/31036452

For those of us who don’t want to end up in the same situation as parents in that movie, can anyone provide scientific evidence that the benefit of today’s full vaccination schedule far outweighs the risks?

Posted by mm57 | Report as abusive

k9quaint, thanks for your answer, but I think you missed my points.

The question is –

- if there is a mortality rate of 9 /100,000, what would it have been if everyone in the community was vaccinated?

What % of the children who died were vaccinated? Not vaccinated?

What % of unvaccinated children have parents who object to vaccination vs how many don’t get it because we don’t have universal health care?

Again, if any epidemiologist would like to answer: what is the attributable risk of death from vaccine-preventable-diseases (VPD) for a vaccinated child as a function of the % of unvaccinated children in that community? I’m betting it is pretty low if it has been studied. If I’m wrong, I’ll learn something.

Please don’t use the appeal to authority argument, since math is the same across all fields, as far as I know.

Posted by cycle | Report as abusive

Cycle: First of all, my argument is not an appeal to authority, you cited a random number. Now you have now backed it up with the “I don’t know but I am betting that” defense.
Let me cite a number to you:
There is a 100% certainty that you will die if someone is not vaccinated.
You may not dispute this statistic because you are not an epidemiologist. It also happens to be true, but irrelevant. :)

You are focused on mortality when you should be focused on exposure to the contagion. The mathematical function of the spread of these diseases has been studied in depth for decades. You can read about a popular model that has been around since the 1920s here:
http://www.osc.edu/education/si/projects  /epidemic/index.html
Moreover, why are you asking for math that is readily available from Google? Why are you demanding that epidemiologists come here to educate you when you can go to the medical institutions and read what they have to say about it? The preponderance of medical research points to vaccine efficacy. If you don’t believe it, spend some time in central Africa without your shots.

Also, you conflate the risk to society at large vs the risk to the students and community of Waldorf. Allowing a small pocket of people to be unvaccinated represents a small absolute risk to the 7 billion people on the planet. However, would you be comfortable sending your child to Waldorf? Probably not, since you can’t be sure that your child is immune even if they were vaccinated. The risk of severe complications from these diseases (blindness, etc) is very real. But what about letting them play at the neighborhood park that is also attending by students from Waldorf? Or a play-date with someone who had a play-date with someone who has a nanny who’s sister works at Waldorf? FYI, I live within 4 miles of the school so this particular story has real implications for me, not just theoretical ones.

That was why the article was entitled: “Most dangerous school in Los Altos”. The danger of infection is local, but the attitude behind it constitutes a persistent barrier to advancement against communicable diseases around the world.

Posted by k9quaint | Report as abusive

OK, let’s take measles for an example. CDC data 2008.

131 cases
9 in vaccinated
% population vaccinated 90%

this is for 2008

Assume a 100% increase in measles rate in vaccinated individuals for a drop of 10% of population immunized to 0.8.


140 cases
18 vaccinated
A guesstimate to get into the ball park.

Population of US 307006550

The theoretical absolute increase in risk for a vaccinated person is about 4×10-8 when the rate of measles doubles in vaccinated individuals due to a drop in vaccination rate from 90% to 80% in this thought experiment.

I learned long ago when interpreting risk that it’s a good idea to crunch the actual numbers to get an idea of how much real life impact a finding may have.

Posted by cycle | Report as abusive

“Assume a 100% increase in measles rate in vaccinated individuals for a drop of 10% of population immunized to 0.8.”

Huh? Why not assume a 10,000% increase?

Here’s a simple recipe for you:
(1) Take a single active case of measles.
(2) Expose 300 non-vaccinated children.
(3) Watch 100 active cases of measles traipse through the broader community, happily infecting as they go.

There’s your 10,000% increase. It might not be wholly accurate (depends strongly on the transmission rate in a population without prior exposure or vaccination), but I don’t see any hint of epidemiological calculations in your thought experiment either.

Measles killed more Native Americans than guns did. What percentage increase is that? Do the results fit your thought experiment?

Posted by TFF | Report as abusive

We are lucky that enough of the population is vaccinated that we can avoid major outbreaks of various vaccine preventable diseases. Sure, I’d like to see vaccines offered to everyone under a universal health care system to increase the rate to as close to 100% as possible.

But based on my amateur risk analysis, I would not avoid sending my child to a Waldorf school because my child would be vaccinated, and the increased risk of infection in a vaccinated child is negligible, unless you belong to the Anti-Meteorite Society and wear a hard hat outside.

Posted by cycle | Report as abusive

cycle, you do realize that your “amateur risk analysis” is complete bunk?

Try the following slightly more complicated thought experiment:
(1) Every infected person exposes 20 others.

(2) Of those exposed, 1% of the vaccinated individuals catch the disease but 10% of the non-vaccinated individuals catch the disease. (This would imply a vaccine that is 90% effective.)

With 100% vaccination, each new case (imported from a country with spottier vaccination) would generate 0.2 additional cases. This is a geometric series with a = 1 and r = 0.2, for S = 1.25.

With 90% vaccination, each new case would generate .18 new cases among vaccinated individuals and .20 new cases among non-vaccinated individuals. Now r = 0.38 and S = 1.62. With 70% vaccination, each new case would generate .74 new cases and S = 3.85.

With 50% vaccination, each new case generates .10 new cases among vaccinated individuals and 1 new case among non-vaccinated individuals. r = 1.1, S = infinite (endemic).

Vary the transmission rate and the number of people exposed (as well as the effectiveness of the vaccine) and you can get a wide variety of results, but for ALL realistic choices of variables there is a tipping point. As you near the tipping point, the number of cases explodes.

At that point, everybody gets exposed sooner or later. The proportion of vaccinated individuals that contracts the disease is merely the complement of the effectiveness of the vaccine. Thus a vaccine that is 90% effective (better than most) would result in 10% of the vaccinated population eventually contracting the disease.

You cite 9 cases, and assume that in the worst case it might increase to 18 cases.

What is 10% of 300 million?

Posted by TFF | Report as abusive

Felix – you mentioned contraction of preventable diseases among infants too young to be vaccinated due to contact with non vaccinated kids; this has actually happened in Australia in many cases. Some of Australia’s highest infection rates for things like whooping cough (sorry, don’t know if there is an english or american word for it) are in Byron Bay and other similarly alternative, luddite-esque towns in Australia.

Posted by willderwent2010 | Report as abusive

TFF, you’re using math. They don’t teach math in Waldorf schools until 7th or 8th grade. And even then, it’s not complex enough to solve those equations.

Posted by KenG_CA | Report as abusive

TFF, you are invoking a complex structural model of transmission which makes many more assumptions than I. It’s not particularly convincing though it sounds erudite.

In 1989, the vaccine coverage rate was estimated to be about 70% and the number of cases in vaccinated individuals was 8,617. If we have a vaccine coverage of 90% at this point, it suggests an additional risk of 5×10-5 in vaccinated children when you drop vaccination rate from 90% to 70%.

I think I’m in the ball park while you are circling Venus with 10% of 300 million.

But then again, I’m not an epidemiologist.

Posted by cycle | Report as abusive

I think there’s a spectrum of how people view risks vs. benefits concerning vaccines. There is a small group of people who view vaccines as all risk all the time and decline all vaccines for their kids and always will.

There is a larger group who selectively vaccinate by skipping or delaying some vaccines after doing a risk/benefit analysis based on their circumstances. These are people who will likely change their behavior when outbreaks of vaccine-preventable diseases become widespread and serious complications occur in significant numbers. Many of these parents will choose to get vaccines for their previously unvaccinated children.

Also, I should mention that I pay close attention to this because my young daughter is immunocompromised and can’t get all her vaccines. As cycle pointed out, there are many children who aren’t fully immunized because they are in families living in poverty. These kids, unlike kids living in affluent households with good diets and healthy lifestyles, are more vulnerable to illnesses and more likely to contract a vaccine-preventable illness if exposed.

This year there have been a relatively large number of measles cases. One case was a Waldorf student in Virginia who spent a day in school while contagious. None of the other kids at the school caught measles from the infected student even though the vaccination rates at the school were low.

Another case was a Somali child who contracted measles outside of the country and after returning to Minnesota infected another child at a drop-in childcare facility who went on to infect other individuals living in a homeless shelter and the outbreak spread further from there. Vaccination rates for children are relatively low in the Minnesota Somali community like the Virginia Waldorf school and yet the outcome was so different.

Vaccination rates matter, but they aren’t the only thing that matters when it comes to the spread of vaccine-preventable diseases. As the mom of an immunocompromised child, I’ve just reached the point where I can’t help but think, at least for the time being, that it’s a waste of time and energy to focus on the handful of well-educated parents who are selectively vaccinating and/or the tiny number of parents who decline all vaccines while virtually ignoring the relatively large numbers of poor, vulnerable children whose parents would get them vaccines if they could access them more easily.

Posted by MCLB | Report as abusive

“TFF, you are invoking a complex structural model of transmission which makes many more assumptions than I. It’s not particularly convincing though it sounds erudite.”

No, it is a simplified model, and I noted that the results depend strongly on the inputs. I can’t claim credit, however, as you will find something very similar in any elementary chapter on epidemiology. (Yet another value of a college education — you pick up a wide array of random knowledge.)

“In 1989, the vaccine coverage rate was estimated to be about 70% and the number of cases in vaccinated individuals was 8,617.”

Ah, some data! In that epidemic, there were 16,400 cases of measles. If your number is correct, half of them came in vaccinated individuals. Would want more details to understand that better, but your example quite clearly emphasizes the difference between 90%+ vaccination rates (perhaps 100 cases annually) and 70% vaccination (16,400 cases). It is blatantly non-linear.

“I think I’m in the ball park while you are circling Venus with 10% of 300 million.”

Why? Wouldn’t be that many cases every year, but an initial epidemic could approach that number. Once the level of immunity drops to the point that the cases MULTIPLY (r > 1) rather than SHRINK (r < 1), an epidemic is limited only by the size of the population it has to run through. And the fact that after catching the disease you will either be immune or dead.

You will note, however, that my model didn’t reach that number until a 50% vaccination rate, and the precise number depends strongly on the inputs. Was a proof of non-linearity, which ought to be obvious, not a prediction.

Posted by TFF | Report as abusive

TFF, I’m not arguing that transmission rates are non-linear. If vaccination rates dropped to 50% I agree you would have to add a few zeros to the 8617 number above.

I did a very rough analysis of risk and the excess risk of illness in a vaccinated individual after a drop in vaccination from 90% and 70% is probably very small. It would not be high enough to prevent me from accessing a Waldorf School in spite of this alarmist article.

I’m right there with MCLB on this: “…that it’s a waste of time and energy to focus on the handful of well-educated parents who are selectively vaccinating and/or the tiny number of parents who decline all vaccines while virtually ignoring the relatively large numbers of poor, vulnerable children whose parents would get them vaccines if they could access them more easily..”

I wonder what the excess risk of morbidity and mortality is in the US for NOT offering universal health coverage.

Posted by cycle | Report as abusive

Then we are essentially in agreement, cycle. A vaccination rate of 90% offers pretty good “herd immunity”, with disease outbreaks getting stamped out pretty quickly. A vaccination rate of 50% does not, allowing the disease to spread widely through the population. At that level, a large proportion of the vaccinated population will be exposed — and the number that contract the disease will depend on the effectiveness of the vaccine (typically below 90%).

In between, there is a large grey area in which the degree to which an outbreak spreads depends on a number of factors specific to the disease itself. For some diseases, a 70% vaccination rate might be sufficient to limit outbreaks to a few thousand. For other diseases, a 70% vaccination rate merely slows the spread of infection. It also depends on the distribution of the vaccination. If the non-vaccinated cluster in communities with others, then the risk of a large outbreak increases dramatically. You only need ONE available vector of exponential increase for that to happen.

Your rough analysis of risk, based on a single outbreak of a single disease and some off-the-cuff logic, offers an insufficient basis to generalize. To properly assess the impact of a 70% vaccination rate you need many more details and a much more complicated model.

“It would not be high enough to prevent me from accessing a Waldorf School in spite of this alarmist article.”

Is up to you… Your chance of encountering somebody with the measles in this country is quite small. But your chance increases dramatically if you live in a community with a low vaccination rate (23%, not 70%). Epidemics will spread more rapidly through communities that eschew vaccination than through communities that do not, so if *any* child in that school encounters somebody with the measles, there is a good chance they will bring that back to share with all their peers. Your chance of contracting the measles when living in a population like that easily goes up by 100-fold (though it is still a small chance).

“virtually ignoring the relatively large numbers of poor, vulnerable children whose parents would get them vaccines if they could access them more easily”

Where are these poor, vulnerable children? Here, at least, vaccinations are required to enter kindergarten or a licensed day care. Vaccination rates for the poor presumably approach 100% once the children reach school age. (And vaccinations are easily accessed at no cost through community clinics.)

“I wonder what the excess risk of morbidity and mortality is in the US for NOT offering universal health coverage.”

Definitely elevated, however the cost of a vaccination program is orders of magnitude cheaper than the cost of universal health coverage.

Posted by TFF | Report as abusive

TFF,You made a good point about how poverty affects vaccination rates for school-age kids. I do know for the younger kids (19-35 months) the CDC has identified a disparity in vaccination rates between the kids living in poverty compared to other kids but I don’t know if that holds up for school-age kids. Also, I don’t know how well-enforced the vaccine requirement for school attendance is. I suppose it varies somewhat.

Posted by MCLB | Report as abusive

In my experience, MCLB, the vaccine requirement is strongly enforced. Our youngest began preschool when he was 3 — but his birthday was days before the start of school and the doctor’s appointment (and annual vaccinations) were scheduled later that week. Couldn’t walk through the door until they were wholly up to date.

May vary by state, though.

Posted by TFF | Report as abusive

I think it likely varies by state, county, school district and school. In our case, when my daughter was entering kindergarten she was on a pretty high dose of an immune-suppressing drug and had been all summer. So I turned in her shot record and just gave the school secretary a verbal explanation of why she didn’t have all the required shots (didn’t turn in a medical exemption or sign a personal exemption) and the school (public) was fine with that and had no problem with her attending. I just told them I’d give them revised records when/if she was able to get caught up.

This is pure speculation because I don’t live in a high poverty area, but I imagine that schools with a lot of students living in poverty are somewhat flexible about the vaccine requirement. I doubt that the school personnel would be too quick to turn away children who need the stability of school, not to mention the two free meals. Here’s something from a Chicago Tribune article earlier this year.

“At Paul Revere Elementary School on Chicago’s South Side, where nearly all of the families are low-income, about 20 percent were not fully vaccinated against measles.

Many parents can’t read, so understanding and filling out forms can be difficult, said Revere Principal Veronica Thompson. Knowing when a child is due for a shot is another problem.

‘Parents are moving frequently, losing paperwork and do not understand the process,” she said. “When they have multiple children, some are due for immunizations and others are not. Anything that makes it a tedious process for them really has an impact.’ ”

http://articles.chicagotribune.com/2011- 06-18/health/ct-met-vaccination-rates-sc hools-20110618_1_measles-vaccinations-va ccination-rates-herd-immunity

Even though the small private schools may have higher rates of kids who aren’t wholly vaccinated, there aren’t very many kids who attend those kinds of schools. Unfortunately, the sad reality is that there are many children living in poverty so when there’s a school with 20% of students without all their vaccines, that adds up to a lot of kids. And these are kids who aren’t necessarily consistently getting a healthy diet, or a good night’s sleep or time outside to play and be physically active, which makes them more susceptible to all illnesses, not just vaccine-preventable ones.

If you’re interested, you might want to check out the CDC’s reports on vaccine coverage. Here’s a link to the most recent one on kids 19-35 months old. http://www.cdc.gov/mmwr/preview/mmwrhtml  /mm6034a2.htm?s_cid=mm6034a2_e&source=g ovdelivery It helps me to keep things in perspective and to feel reassured knowing that vaccination rates are high and rising and that the numbers of kids not receiving any vaccines is so low (less than 1%).

Posted by MCLB | Report as abusive

Nice discussion. I’m on the side of the Waldorf School of the Peninsula on this one- with a caveat. But first, what do these statistics mean? They mean that only 23% of the school has ALL their shots. This includes an inoculation against the sexually transmitted disease, Hepatitis B. The hospital wanted to give this to our new born! That is absolutely ridiculous. The number of inoculations that are required are astounding and to have them all at once is dangerous. So they have to be spread out. My wife and I held off any immunizations until our children were 2 years old because we felt that their own natural defenses needed some maturation before introducing all the mercury many of the shots still have. So, our kids were not at 100% when they started school and we had to get a waiver for them to attend. 6 months into kindergarten and my youngest, as well as all my children, are now finally are at 100%.

The Waldorf school is for rich, crunchy liberals who feel like our society pushes policies for the benefit of the drug companies as much as, if not more so, than our health. There is some truth to that. I’ve heard of having chicken pox parties so that one infected child can help others without the vaccine develop their own resistance the old fashioned way. This is a bit extreme and a threat to the frail, but otherwise not life threatening.

My point is that you have to understand what these numbers mean. 23% sounds very dangerous. But if that means the children are only missing the chicken pox and hepatitis B vaccines, I’m thinking we really don’t have anything to worry about.

In addition I’d like to point out that the fanatic pro vaccine policies in the US are a mass experiment. The high rate of autism on the Peninsula has lead many to believe that the combination of some vaccines might have been a factor. So while we are trying to prevent an epidemic, we could have and may potentially in the future create one. A little caution might not be a bad thing.

Posted by LEEDAP | Report as abusive

“The high rate of autism on the Peninsula has lead many to believe that the combination of some vaccines might have been a factor.”

Wasn’t the study that “discovered” that connection finally debunked as a fraud?

If autism is truly rising — and it may simply be diagnosed more frequently than in the past — then any number of factors could be in play. Without evidence connecting autism to vaccines, I would hesitate to jump to that conclusion.

Posted by TFF | Report as abusive

Hep B isn’t just sexually transmitted. The reason they want to give it to your newborn is because of vertical transmission, that is, transmission of Hep B from mother to child. In many cases, women go untested for Hep B during pregnancy. In another 30-40% of infant Hep B cases, the actual transmission method is unknown.

Really, what we’re dealing with here is people who still believe a widely debunked theory about vaccines, and who think that the risk of a vaccine is higher than the risk of infection (demonstrably false), and in doing so, effectively increase risks for everyone, especially immuno-compromised kids.

Little Richie Richie probably won’t die of whooping cough, measles, mumps, or hep B, because mommie and daddy have the financial resources to get the best available care. The same can not be said to other people they may spread the infection too.

There are children all around the world in developing countries whose parents are desperate to get a vaccination, but can’t. It will take a serious epidemic and a bunch of anti-vax kids dying off, before this sad state of affairs rights itself and people wise up and stop believing in pseudo-scientific newage bullshit.

Posted by cromwellian | Report as abusive

Late post, because I just found this blog and am shocked by the erroneous and misleading information about the school and vaccine requirements, in general. I am a public health nurse and a school nurse, so I know of what I speak.
1) This chart is misleading. When parents opt for an alternative vaccine schedule, it is recorded not up-to-date. But it does not mean the kids are not vaccinated at all. It means they have had some vaccines, but not all. Many many parents are vaccinating on a different schedule and you need to know that percentage before you can say that the kids are not vaccinated.
2) LaraR is wrong. In the state of California, kids can come to school if they are not immunized. This is the LAW. They just need to sign a waiver. Public schools are just not honest with their attendees about informing them on the law.
People, including reputable bloggers, need to check out the facts before publishing inflammatory words.

Posted by ClosetCon | Report as abusive

The “waiver” is called a “Personal Belief Exemption”, or PBE, and the PDF linked to in an early comment shows that 32 of the 44 kindergarteners at WSotP have it. Ten are up-to-date and only *two* are in the other category “conditional.”

Among those 32, sure, it may not be that none of them have *any* of their shots. But it’s pretty fair to assume that they’re missing a lot of them or they wouldn’t bother getting this exemption.

I think this blog post is entirely justified by the data we have.

Posted by kevinb9n | Report as abusive

Update 2 “… Which seems to have had the unintended consequence that parents who don’t want to immunize their kids all end up sending their kids to the Waldorf School, …”

Whaaat? I think the $18k – $20k a year tuition alone would prevent that from happening! What a ridiculous and ignorant statement. That alone sizes up the article. If any info here is true, it is certainly discredited now by this wacko statement.

Posted by DotOrg | Report as abusive

It is truly unfortunate how intolerance, fear, and statistics can control others. In the 1980′s I spoke to an East German couple who said that if your child could have a “Rudolf Steiner” education aka Waldorf, that it is the best education one could possibly give your child. At that time, under Communist rule, there was a huge underground movement of Waldorf educators and students who would have given up their lives to give their children this education. In Germany, the government supplements the cost of going to this school so that all have the opportunity to attend. When the wall came down, Waldorf schools flourished in East Germany. Unfortunately, living in America is costly. I believe the immunization factor is a separate issue. Each family and person has the right to decide what is good for their child. I, personally, have chosen to never get influenza vaccines. I am surrounded by people who get the flu shot and 2 months later catch the flu. I haven’t had the flu in 5 yrs, and realize that the only time I get sick is when my immune system is weak…created by not getting enough sleep, not eating right, or overworking, etc. In any case it is a choice, and there are parents that later in life change their mind, and get immunizations for their children. I am truly sorry that you have created conflicts between a wonderful school and immunizations.

Posted by Setsuko | Report as abusive

This article makes me really sad. Any parent can sign a waiver in the public school which allows them to enroll without immunizations. Maybe educated people are questioning the status quo. My daughter had a seizure IN MY ARMS when she was 8 weeks old…”a vaccine induced encephalopathy due to the Pertussis vaccination” they called it. Sound fun to you? I don’t vaccinate anymore. Subsequently, my kid went to a public school and then left that shame of an education system for a Waldorf School. You should concentrate your efforts on “How Public Schools are Failing to Educate our Kids and Our Country.”

Posted by OntheTrail | Report as abusive

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