Vaccine exemptions in California threaten herd immunity

I don’t know if it’s confirmation bias, faulty memory, or if my individual impression is correct, but it seems to me that over the years I’ve been blogging that stories like this one seem to be becoming depressingly more common:

Getting inoculated for diseases such as whooping cough and measles used to be a childhood rite of passage that few questioned. Now with shifting parental attitudes about vaccine safety, a growing number of California children are entering kindergarten without shots.

The trend worries public health officials because of the link between immunization rates and infectious outbreaks. As they grapple with the worst whooping cough surge in half a century, they are fighting back with outreach campaigns to promote vaccinations.

The Watchdog Institute, a nonprofit investigative journalism center based at San Diego State University, found that waivers signed by parents who choose to exempt their children from immunizations for kindergarten enrollment have nearly quadrupled since 1990. California allows parents to opt out of some or all shots on the basis of personal beliefs, be it religious objections or distrust of the medical establishment.

That California is ground zero for vaccine rejectionism is not a surprise to me or anyone else who’s paid attention to the issue of the anti-vaccine movement. Indeed, when I last wrote about this a year and a half ago, I drily observed that when the outbreaks begin, they’ll probably start in California. At the time, I was writing about an LA Times article that described the skyrocketing numbers of “philosphical” exemptions being claimed by parents in California. The story laid out the problem in considerable detail. Affluent parents in affluent suburbs, never having seen the diseases against which vaccines would protect their children, decide that these diseases are not a threat, confident in the delusion that there’s no way their children could ever suffer from these horrible diseases. Oh, no! Those are diseases for children in Third World ghettos, not their precious children. After all, they’re affluent and can afford everything their children need, and they care so much about their children. Besides, Jenny McCarthy and her fellow travellers in the anti-vaccine movement tell them that vaccines cause autism. Obviously vaccines are nothing more than a plot by The Man to make lots of money and turn their children autistic! Last year, unvaccinated children were clustered in certain areas. For example, at Waldorf schools (or, as I like to call them, pathogen repositories), vaccine exemption rates can be as high as 82%. Otherwise, the highest exemption rates appeared to be in Sonoma County, although Los Angeles and San Diego Counties were also up there.

What about this year? This year, it looks as though San Diego County has an exemption rate consistently higher than the state average, just as it has been for quite a while. The Watchdog Institute found:

  • Personal-belief exemptions granted to entering kindergartners reached a record high of 10,280 in public and private schools statewide last fall, up from 2,719 in 1990.
  • San Diego County’s exemption rate is 2.64 percent, compared to 2.03 percent statewide. While those percentages seem small, public health officials are concerned that unvaccinated children tend to cluster in certain areas, creating pockets of vulnerability.
  • Schools with the highest exemption rates tend to be private schools, public charter schools, and traditional public schools in affluent areas. Among schools with 25 or more kindergartners last year, 14 had immunization opt-outs for more than 15 percent of their kindergarten class. The top was the Waldorf School of San Diego in City Heights, at 51 percent.

A 51% exemption rate implies that only 49% of the children at the Waldorf School of San Diego are vaccinated, far below a rate that even has a prayer of maintaining herd immunity.

Of course, anti-vaccine parents both demonize and have unrealistic ideas about what vaccines can do, which is part of the problem. They demonize vaccines as the cause of autism, autoimmune disease, and asthma, along with all sorts of other health problems, even though there is no scientifically credible evidence linking vaccines to autism or any of the other conditions attributed to vaccines. Yet, at the same time, they justify their refusal with the implicit belief that vaccines are 100% effective. I refer to this as an “implicit” belief because a frequent argument made by anti-vaccine parents when it is pointed out to them that they are endangering other children is that those other children are vaccinated; so how could their precious baby ever be a threat to other children? The reason, of course, is that no vaccine is 100% effective. Some, like the MMR vaccine, are “only” around 90% effective. Now, in medicine, 90% effectiveness is in general excellent, about as high as one can expect from any intervention. It’s not 100%, though. Worse, pockets of unvaccinated children provide a repository for vaccine-preventable disease that can infect other unvaccinated children, as well as vaccinated children who, for whatever reason, did not develop effective immunity due to their vaccination.

Failure to vaccinate also endangers the unvaccinated children as well. Last year, in fact, this risk was quantified in a study that found that unvaccinated children have a 23-fold elevated risk of catching pertussis compared with vaccinated children. Given how nasty and contagious pertussis is and how safe the vaccine is, there really is no good reason not to vaccinate at least against pertussis. Of course, parents have their reasons not to vaccinate, virtually all of which rely on either exaggerated fears of autism, a woo-ful belief that “natural” must be better, and, perhaps, one of the most common delusions among the “natural health” set.” This last delusion is one shared by Bill Maher and consists of the belief that if you eat the right foods, excercise, and keep yourself healthy “naturally,” you can’t get sick from vaccine-preventable diseases. In other words, good living (whatever that means) is as good as any vaccine in their view. In fact, one anti-vaccine mother named Yvonne Haines was interviewed in the article is quoted thusly:

“We do find that the unvaccinated kids are extremely healthy because their bodies have been allowed to develop their own immune system, rather than relying on vaccinations, which are like substitutes,” she said.

Uh, no. They aren’t any healthier than vaccinated children, and microbes don’t care how “healthy” your children are.

Yes, it’s true that it’s better to be well-nourished and in good physical shape than not. It will even help fight off disease. But it won’t protect your children the way a vaccine will. You can have the healthiest child in the world, but if that child is exposed to, for example, measles, which is highly contagious, chances are that your child will catch the measles. Ditto pertussis. Unfortunately, what public health officials are fighting against is attitudes like this:

Rebecca Estepp of Poway, a mother of two boys 12 and 10 years old, is familiar with that logic, but she cannot square it with her maternal instinct.

After her first son suffered adverse reactions from vaccines and developed autism, she decided to not to go through with the full schedule of immunization for her second son.

“I don’t know if there is an acceptable level of collateral damage in the war against infectious diseases,” said Estepp, who is also the government and media relations manager for SafeMinds, a nonprofit that investigates the link between vaccine ingredients and neurological disorders.

We’ve met Estepp before. She frequently lays down swaths of burning stupid about vaccines of this sort. She’s so utterly convinced that vaccines caused her child’s autism that nothing will convince her otherwise. Meanwhile, she continues to promote the false dichotomy that it’s a choice between “autism and the measles” and that she’d pick the measles. In actuality it’s a choice between measles and not getting the measles, given that the MMR vaccine is, by any measure, incredibly safe. It is also a choice of preventing measles at a very low risk versus the risk of getting the measles and its potential complications. Nonetheless, Estepp decided that she’d put her her son at high risk of contracting measles, which, contrary to the misconception, is not a benign disease. Worse, she did it because she believed in a myth promulgated by the anti-vaccine movement.

One aspect of this article that perfectly encapsulates the thinking of a lot of these crunchy anti-vaccine moms is an interview with Johannes Lasthaus, Waldorf’s administrator:

Schools that top the list of highest exemption rates in the county in 2009 are almost all either private or charter schools. The private Waldorf School of San Diego, where tuition ranges from $7,500 to $14,000 a year, has the highest exemption rate.

“Our parents are really educated. They are trying to make their own decisions, not being influenced by pharmaceutical companies,” said Johannes Lasthaus, Waldorf’s administrator.

His school, he noted, has had no outbreaks and maintains a policy of keeping sick children at home.

“It’s all about people’s right to choose what is right for their child and their family and really respecting people’s choices, whether they choose to vaccinate or choose not to vaccinate,” said Julie Joinson, Waldorf’s director of admissions, speaking for herself. She noted that her daughter, 14, who has never been vaccinated, is “super healthy.”

“It’s not that I think that vaccinations are terrible,” Joinson said. “If I lived in a third-world country with open sewage running down the streets, I would probably vaccinate my child. At this point, I really have concerns about what goes into vaccinations.”

With all due respect, Ms. Joinson has “concerns” because she doesn’t know what he’s talking about. Think of it this way. Before the polio vaccine, the U.S. was not a “Third World coutnry with open sewage running down the streets.” Yet, as recently as the 1950s, every summer there were polio scares in which public swimming pools were closed down. Periodically there were polio epidemics, and there were thousands in iron lungs. Does Ms. Joinson know what ended that? No, it wasn’t sanitation. Sanitation was just fine in the 1930s, 1940s, and 1950s. It was vaccines. Similarly, it was the vaccine that eradicated smallpox. The fact is that the single biggest source of microbes causing vaccine-preventable diseases is not raw sewage, as Ms. Joinson seems to think. It’s other children. These days, it’s unvaccinated children far more than vaccinated children.

As for the Waldorf school having had no outbreaks, it’s only a matter of time. In fact, Waldorf schools, which are widely known for their resistance to vaccines and scientific medicine, have had a number of outbreaks. For example, just this year there was a measles outbreak in Essen, Germany where the majority of cases were linked to a Waldorf school. In 2008, the East Bay Waldorf School was shut down due to a pertussis outbreak, and a Waldorf School in Salzburg, Austria was hit by a measles outbreak. There are numerous other examples, and, as vaccine uptake falls, Mr. Lasthuase is fooling himself if he thinks his school is not at risk, no matter how strict he is about sending children home when they appear to be sick.

I believe that we are approaching a tipping point. Although vaccine uptake is generally high throughout the U.S., there appear to be more and more pockets of vaccine refusal, leading to populations of unvaccinated children who can serve as vectors to result in outbreaks as herd immunity breaks down. Although I doubt that vaccination rates will fall to the point where mass epidemics are likely, although Generation Rescue and Jenny McCarthy are sure enough doing their best to make sure that happens (if you don’t believe me, just wait a while to see what sorts of comments appear on AoA after this post triumphantly trumpeting this article). There are likely to be more and larger outbreaks of vaccine-preventable diseases.

It’s the face of the future. I hope I’m wrong, but I fear I’m not.