Did you miss me?

It would be a world-class understatement to tell you that I’ve been busy lately. I’ve traveled from one side of the planet to the other and back. I’ve been chasing viruses and bacteria wherever that three-lettered health organization has needed me, and I’m exhausted. So I’m back home to recoup before heading out into the cruel, cruel world again as the freelance epidemiologist I’ve become.

Before I go sip on some tea and watch a movie or two on HBO, I wanted to tell you that the Zika outbreak in the Caribbean seems to be waning. Don’t be fooled, however. The mosquitoes are there, and so are the people. Sexual transmission is likely ongoing, so this lull in activity is only temporary. Zika will come back soon enough, and it’s going to make a mess of things. Just wait until it gets hot in the South.

When that happens, we’re going to have ourselves a good, old-fashioned, all-American outbreak. You know the type? Where politicians don’t know what to do and only do the wrong thing? Especially with Trump in the White House. I’m getting the popcorn ready.

Next time, I’ll tell you all about how the new territorial epidemiologist of a US Territory doesn’t believe Zika is a thing. (I wish I was joking.)

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It’s a small world after all!

When Andrew Jeremy Wakefield told us that it was his gut feeling that the MMR vaccine caused autism, I doubt that he had any idea of what he was about to unleash on the world. I really don’t think that he wanted to trigger outbreaks of vaccine-preventable diseases in places where vaccines had suppressed those diseases out of epidemic range and into sporadic range. I bet he was in it for the money. Get people to take less of the MMR and more of the vaccine that he was trying to patent. Like any industrialist, he wanted to crush the competition and give the people a reasonable alternative.

That’s my theory, anyway. The truth could be more sinister and Andrew Jeremy Wakefield really was trying to cause outbreaks of measles like the one that engulfed Wales in 2012-13. That outbreak resulted in a little over 1,200 reported cases. The true number is probably higher, since not everyone sick was tested and a lab confirmation is necessary to call a case a “confirmed case.” In a country of just over 3 million people, the incidence of measles during the time period of the outbreak was about 40 cases per 100,000 residents. If you ignore the differences between Wales and the United States, this would translate to an outbreak of 128,000 confirmed cases in eight months in the United States. Like in the US, measles was declared eliminated in the United Kingdom at the beginning of this century when the incidence rate was less than one case per 100,000 residents per year.

Because so many people decided not to vaccinate with MMR anymore in Wales after Wakefield’s fraudulent paper on MMR and autism, herd immunity against measles (a very, very infectious disease transmitted through the air) ended, bringing about the Wales outbreak. That outbreak caused a lot of people to become sick and at least one death. (The death rate from measles is about 1 in 1,000, so it stands to reason that 1,200 confirmed cases would lead to one confirmed death.) In the nightmare “all things being equal” scenario in the United States, we could expect about 128 people to die from measles.

Death is not the only measure by which reasonable people should measure the impact of a disease on the population. There are other costs as well. There is the cost of parents missing work because they have to tend to sick children. There is the cost of medical care for those sick children. There is also the cost of tracing the contacts of the cases, and the people who are quarantined because they may be infectious will miss work and school. In the years before vaccines, this all used to cost a ton of resources to our societies. In the time since vaccines, we have been able to devote those resources to other things. It’s why we are living longer. It’s why you can sit comfortably in almost any place in the world and read this blog.

Unless you’ve been living under a rock, you have probably heard about the measles outbreak that seems to have as its epicentre “the happiest place on Earth”, Disneyland. Look at this news report from the San Diego Union-Tribune online:

“San Diego County now has 10 active measles cases, all of them linked to Disneyland visits in December, public-health officials confirmed Thursday.

Six siblings, 22 months to 18 years in age, had arrived Wednesday at the Sharp Rees-Stealy urgent care center in La Mesa with rashes and other signs of measles. Shortly afterward, the county’s Health and Human Services Agency learned of a case involving an adult older than 50.”

The only person in that bunch who was fully vaccinated against measles was the adult over 50. That’s it. The six siblings are not up to date on their vaccinations and, according to the news report, they are not enrolled in any public schools in San Diego County, California. Now there’s a list of places where they went while they were infectious. (A person is infectious before any symptoms appear.) Public health officials are asking anyone who is not vaccinated and was at those places to seek medical attention in order to contain the outbreak. The outbreak now stands at over two dozen people with more cases coming, according to my sources in public health at a national level.

That’s just the tip of the iceberg, folks. This has the potential to turn into the Wales outbreak but at a scale for a country of almost 320 million people. Last year we saw the most cases of measles in a year since the disease was eliminated from the United States. There were over 600 cases and over 20 outbreak. As Ren pointed out, a drop of just one or two percentage points in the proportion of people immunized raises the number of people in an outbreak significantly:

“A paper published in the American Journal of Epidemiology looks at these outbreaks and analyzes what it would take for measles to come back and be endemic in the United States again, or, at the very least, cause sustained epidemics. The paper is titled “Identifying Postelimination Trends for the Introduction and Transmissibility of Measles in the United States” by Blumberg et al. The authors looked at the sizes of transmission chains in outbreaks of measles and developed a mathematical model for determining the infectivity of measles and what several milestones would be for sustained transmission. In the paper, the authors concluded that the average size of a transmission chain is about 2 cases and that about half of cases are imported to the United States. In other words, a case goes out and brings measles and then infects one more person here, on average. Some chains are considerably larger. Other chains are not chains at all but single cases who return to highly immune communities. This assumes that all cases are properly reported to public health, which is not always the case from my experience.

The math used by the authors took into consideration vaccine coverage in the United States as reported by CDC. If they dropped vaccine coverage by 1%, the average infection chain becomes 2.8 people. Bring that coverage down to 93.9% from 95.9% (a decrease of two percentage points), and the chain jumps to a whopping 4.3 people on average. Let that sink in a little. A simple drop in two percentage points in our current MMR coverage pretty much doubles the number of people infected with measles from people who bring it from overseas, according to the mathematical model presented by the authors.”

How low is the immunization rate in the counties in California where the outbreak started? It’s scarily low:

“The trend is especially pronounced in Orange County, where the proportion of kindergartners with their full shots fell from 92.9 percent in 2003 to 89.3 in 2012, and particularly in the county’s wealthy beachfront communities.”

This is way below the threshold analyzed by the paper that Ren reviewed. It’s about 6 percentage points lower, meaning that the outbreak chain on average will be about 60 cases, if you follow the math from the model in that paper. In a civilised society where the vaccine is widely available, those kinds of numbers are nothing short of insane.

So who is to blame for all this? Is it just Andrew Jeremy Wakefield bringing his MMR fearmongering to the United States after being so soundly rejected in Britain, stricken off the medical record and regarded as nothing better than a self-righteous quack? Is it the douchebag pediatricians who for some reason kowtow to “crunchy” moms and dads who are afraid of vaccines? Is is the other douchebag pediatricians who pull “alternative vaccine schedules” out of their asses and tell non-vaccinating parents that it’s okay to “hide in the herd”? Is it the fire science graduates who bloviate about the so-called dangers of vaccines and try to make themselves sound important when they’re nothing more than warm piss flowing down the drain of the truck stop restroom that is anti-vaccine activism?

Yes, it is their fault, but there is more blame to be spread.

It’s the fault of people who think that it is a good idea for anti-vaccine loons like Sherry Tenpenny to travel to Australia and give talks about vaccines, spreading a dangerous message. It’s also the fault of well-intentioned public health professionals who want to defend her free speech right to do so. (Wink, wink, Ren.) People who know that vaccines work but don’t want to engage with the anti-vaccine nutjobs are also to blame for not speaking up and correcting the lies put out there by those hacks. Elected politicians who get a lot of money donated to them by anti-vaccine special interests are also to blame for something that reeks of corruption.

In short, everyone is responsible for this shameful chapter in public health history. We had measles and other vaccine-preventable diseases beat, but we’ve allowed them to come back because we seem to think that parents are the best judges of what is good and what is bad for their children. They’re not. They may be the best advocates for their children, people we can trust will act with in the best interests of the children 99.9997% of the time. However, if they are misinformed fools who think that vaccines are toxic or vaccines make people toxic, or cause autism and whatnot, then they will act wrongly when it comes to what is best for their children and for society in general.

These idiots are walking around with their college degrees in non-science fields thinking that they somehow are knowledgeable in science-related matters because they can google terms and read websites and blogs that confirm their biases without a shred of evidence. They think that they can skip vaccines because, hey, people survived vaccine-preventable diseases all the time. Most of the people who went to war returned from that war. It doesn’t mean that war is not deadly, painful, scarring, and costly beyond human comprehension.

So take a good look at yourself in the mirror right after you read this and ask yourself if you did everything possible to counter the lies and misinformation put out by anti-vaccine luminaries like the morons at Age of Autism or RKF Jr. and his anti-thimerosal brigade. Did you donate to organizations like Every Child By Two, Voices for Vaccines, or Immunize.org? Will you counter your friends and neighbors on whatever medium if they say that vaccines don’t work?

The ball is in your court. It really is, no matter how much or how little you think you influence the world. Eradicable diseases like measles are not being eradicated because the most infectious thing, fear, is being allowed to spread without countering it with the most effective thing against it, knowledge.