The PRNP gene: One reason not all of us make good cannibals

original-fore-tribe-papua-kuruThe story starts in the eastern highlands of New Guinea, back in the 1940s-1950s. A fatal disease called kuru blazed through many villages, and women and children were especially affected. It started with a few months of head and body aches. This was followed by trouble standing and walking. Eventually tremors began, and sufferers lost the ability to get around entirely. Finally, euphoria set in (kuru is sometimes called the “laughing death”). By the late 1950s, more than 200 new cases a year were being reported, and, all told, over 3,000 deaths resulted (in a population that numbered only about 12,000). In some places, few young women were left.

Figuring out what was responsible for kuru was not an easy task. According to the Fore, the group hardest hit by the disease, it had first appeared in the 1920s and spread rapidly.  Researchers noticed that often multiple people in a family were affected, so they started building kuru pedigrees. Complicated genetic causes were proposed. But eventually the strange distribution of the disease (it primarily affected women and young children) shed light on the true culprit: cannibalism. When someone died (say, of kuru) the women and children in the family would prepare their body for the funeral. Part of this preparation involved eating their loved one’s body, in a feast that signified respect for the deceased. The brain, which was the most infectious body part, was eaten by women and children. And the infectious entity wasn’t a bacterium or virus. Instead, it was something entirely different: a prion, or a protein folded in a strange way. Once prions enter the body, they cause other proteins to misfold, until there are enough faulty proteins to cause real problems. The gene that encodes the prion protein is called PRNP, and changes in this gene have since been linked to other prion diseases like variant Creutzfeldt-Jakob disease (aka mad cow disease), fatal familial insomnia, and Gerstmann-Sträussler-Scheinker disease. Kuru and similar diseases are called transmissible sponge encephalopathies, because of the sponge-like effect they have on the brain (shown in the picture below).

BrainSectionsWhile nobody knows for sure how the epidemic started, the current theory is that someone among the Fore happened to develop variant Creutzfeldt-Jakob disease early in the 20th century. When his or her loved ones performed the mortuary feast, they ingested the prion and developed kuru. When they died, the chain continued, and the disease spread across the Eastern highlands. In the 1950s, the Australian government instituted strict, new laws that outlawed cannibalism. After this, the disease started to lose steam. A trickle of new cases continued to appear, however, well into the 2000s. Although the average time from participation in a fateful mortuary feast to the onset of kuru is 12 years, it turns out that the incubation time for kuru can be anywhere from 4 years to over 50! What accounts for that variation? And why did some people who participated in mortuary feasts get kuru, while others did not?

It turns out that the story is not so simple! Those early attempts to link kuru to genes were not so far off after all. At the 129th amino acid residue in the PRNP protein, people either have a methionine (M) or a valine (V). Since we all have two versions of the PRNP protein (one from mom, and one from dad), a person can either be an MM, an MV, or a VV. It turns out that being an MM makes you especially susceptible to kuru. MVs and VVs are both less likely to develop kuru AND if they do develop it, the incubation time is longer. But being an MV is the absolute best. After the kuru epidemic ended, there was a deficiency of MM individuals among the Fore, because so many of them had died of kuru. And it turns out that the finding that MM individuals are susceptible to kuru is relevant beyond New Guinea. Patients who develop variant Creutzfeldt-Jakob disease have also invariably turned out to be MMs!

In 2003, an attention-grabbing paper on the PRNP gene came out in Science. Scientists had already established that, among the Fore, MVs were the most likely to survive the kuru epidemic. When the best genotype to have is one that combines two different types of alleles, it is called balancing selection. Natural selection will often end up keeping both types of alleles in a population; the success of individuals with both versions will result in a “balance” being struck between the two. In the Science paper, a group of researchers said they had also found evidence of balancing selection in the PRNP gene worldwide. What could this mean? The authors speculated that maybe a long history of exposure to prion diseases spread from animals (like mad cow disease) could account for selection that favored MVs. Or MAYBE it was a long history of human cannibalism! This study has been a controversial one. Not everyone agrees with the way the analysis was performed, for example. But it’s pretty interesting.

In short, MMs don’t make good cannibals–or maybe even meat eaters, since they are also more susceptible to mad cow disease. As it happens, you can figure out your genotype using 23andme! If you’ve been genotyped, you can go to the browse raw data page and enter rs1799990It will tell you your DNA sequence at the relevant part of the gene: An “A” corresponds to the M version of the protein, and a “G” corresponds to the V version. I found out I have two As, which means I’m an MM. I’m not cut out to be a cannibal, and maybe I should consider becoming a vegetarian too! That’s the breaks, I guess.

Bach Flower Remedies: Do They Work?

You’ve probably seen Bach flower remedies at health food stores or new-agey sorts of shops. Or maybe your chiropractor or vet has recommended them. bachproducts-allThey’re recommended for all sorts of maladies, including asthma, hypertension, migraines, eczema, allergies, dyslexia. But do they work?

The story behind Bach flower remedies is pretty romantic. Dr. Edward Bach was a Welsh physician with an interest in homeopathy. He believed that many illnesses are caused by things like fear and despair–not so different from how many researchers today view the effects of stress. He also believed that we could develop a new medical system by focusing on cures found in nature. So he abandoned his London practice and headed out into the countryside to investigate the curative effects of flowers. In addition to abandoning city life, he decided to jettison the scientific method and instead use intuition to guide his work. Wandering the lanes of Oxfordshire, he developed a number of flower remedies–many of which you can still buy today.

While Dr. Bach was initially interested in the dew that collects on flowers, he realized that collecting dew drops wouldn’t be very practical if he wanted to reach the masses. So, as the closest large-scale approximation he could think up, he began to make his remedies by putting fresh flowers into water and then steeping them in the sun or boiling them. He also added brandy as a preservative. It’s highly doubtful that the flower remedies contain pharmacologically significant amounts of any flower-derived chemicals–instead, the flowers are supposed to transmit their energy to the water and then to you. So, basically, they are supposed to work via the memory-water mechanism on which homeopathy is based.

A few randomized, controlled trials have actually tested the effects of Bach flower remedies. For example, researchers tried using the Rescue Remedy or a placebo on 100 University students about to take exams. Less than half of the students completed the study, but in those who did, no effect on test anxiety was found. A similar study on test anxiety also found no difference between flower and placebo groups (although even taking a placebo helped soothe students). There is one study that has reported a significant effect of Rescue Remedy in reducing stress in a subgroup of students with very high-anxiety… but if you test enough subgroups you are bound to find a positive result eventually, due to chance alone, so I’m not sure I put much stock in these results.

In another study, researchers randomized 40 kids with ADHD to either Bach flower remedies or a placebo for three months. With only 20 kids in each group though, and with half of the kids dropping out before the three month study was complete, the power to detect any changes in behavior was pretty low. The effect of the flower remedies would have to be pretty amazing to show up. I’m fairly certain a study this small couldn’t have demonstrated a significant effect of ANY ADHD medication.

The good news is that nobody has reported any adverse effects associated with the flower remedies. Since they are essentially water, that makes sense! The bad news is there is not much evidence that they work, except for as a placebo. Some flower enthusiasts point out that so far the remedies have only been investigated for anxiety and ADHD. That’s true. It’s also true that most of the studies done so far have been so small, and getting patients to comply with treatment has been so difficult, that even if the remedies DID work, chances are that the trials wouldn’t detect an effect. Unless you buy that water can holds memories, though, it doesn’t seem likely that even a huge NIH-sponsored trial would pick up any beneficial effect of the Bach flower remedies.

That said, it’s not unusual for 30-40% of people given a placebo to report that they feel better. And Bach flower remedies appear to be harmless. So if someone’s feeling bad and they believe in the potential of these remedies to cure, maybe it’s not such a bad idea to give them a try! Since I don’t see how the placebo effect would work on pets, though, it’s hard for me to see how using the remedies on animals would be of much use. I guess that as an owner, maybe your own anxiety about your pet’s condition could be alleviated in a sort of indirect placebo effect.

Human sacrifice: how did becoming part of the Inca empire change things?

HUACA CHOTUNA 005AI was looking through the May issue of American Journal of Physical Anthropology, when I came across an intriguing title: The variable roads to sacrifice: Isotopic investigations of human remains from Chotuna-Huaca de los Sacrificios, Lambayeque, Peru. Even better, when I glanced at who wrote it, I learned that it was a former lab-mate of mine, Beth Turner!

Human sacrifice was practiced in some pre-Columbian cultures in the Andes. But the nature of human sacrifice varied based on time and place.  Early on, in the Moche culture of Northern Peru, the victim was typically dispatched by throat-slitting, and later on chest mutilation (evidently to remove the heart) became important too. Usually, the victims were youngish-to-middle aged adult males who were probably warriors. Whether they were foreign or local is a matter of some debate. On the one hand, some researchers believe that features of their teeth suggest that they were from some other location. This, paired with the fact that a lot of them had what appeared to be battle injuries, led them to believe that they could be war captives. On the other hand, analyses of things like mtDNA, archaeological context, and stable oxygen isotope values indicated that the victims WERE local, and the Moche were sacrificing one another.

Whether the Moche victims were local or not, it’s clear that the Inca culture, which rose to power later in the South Central highlands, did things differently. They focused on juveniles and young adult female victims. They also drew their victims from other locations–apparently, being especially beautiful could make you a prime target, and having someone chosen from your community could be viewed as a sort of honor by subject groups. Once selected, victims were celebrated at ceremonial rituals and feasts in Cusco before being sent to the sacrifice. By measuring stable isotopes in their remains, researchers can actually detect a shift from a commoners’ diet (prior to being selected as a victim) to an elite diet. And this change in diet sometimes started as much as a year before death. Even if it was viewed as an honor, it doesn’t seem like the awareness that you are being fattened up–like Hansel in the fairy tale, only for much longer–could have been very pleasant.

Turner and colleagues got the opportunity to study human sacrifice at Lambayeque, an important political/religious site in northern coastal Peru. This site is particularly interesting, because during the period they studied, different cultures were meeting there. The Inca had recently gained control. The remains of 33 sacrificial victims were unearthed from this period (they’re shown in the picture above, taken by Miguel Mejia), and they were unusual for this area in that they were primarily young and female. This emphasis seemed Inca-like. Other features of their sacrifice seemed Moche-like, though. They exhibited a variety of traumatic injuries that included throat slitting and chest opening. And evidence of flies around the remains of the victims suggested that their bodies were allowed to decompose/dessicate for about a month prior to being interred (also normal for Northern Peru). So what was going on here? Did the emphasis on young and female victims indicate that the Inca takeover changed the way that sacrifice was performed? If so, did that mean that Lambayeque began to draw its victims from other places, preparing them ahead of time for the sacrifice?

In order to answer these questions, Turner took rib samples and, where possible, hair samples from the remains and used them to perform stable isotope analysis. Their results suggested that the individuals had eaten a varied but typical coastal diet. Unlike the typical Inca victims, there was no evidence that their diet changed significantly prior to the time of death. There was also no indication that the Lambayeque victims came from anywhere but in the region. Given the stable isotope data, Turner and colleagues hypothesized that even though the site was under Inca rule, many local sacrificial customs may have remained in place. The individuals selected for sacrifice may have reflected Inca ideas about ideal victims, but the method of killing (throat slitting and chest opening), as well as the way that the bodies were treated after death, had deep roots in the area. And, in Lambayeque, it doesn’t appear that the victims were chosen from a distant locale and prepared for sacrifice a year ahead of time, Inca-style.

I think we’re all used to reading about how the confluence of cultures has affected daily life in different locations. But I’d never thought about how the logistics of something like human sacrifice would be affected by being absorbed into an empire. This was a gruesome but very interesting read!

Bacteriophage therapy: An idea whose time has come?

220px-PhageBacteriophages are viruses that attack bacteria–their name means “bacteria eater” in Latin. Here, you can see a bunch of bacteriophages on the surface of a bacterial cell. They look sort of like balloons tethered to the surface of the moon. They were discovered near the dawn of the twentieth century, and at first they enjoyed some spectacular therapeutic successes. Felix d’Herelle, one of the men who discovered bacteriophages, treated four dysentery patients with them in 1919. Soon after, he used bacteriophages to treat outbreaks of cholera in India and plague in Egypt. In the U.S., phage trials were performed at Baylor, and the researchers involved were impressed by phage therapy. It didn’t always work so well in practice, though. Phage therapy can be tricky. The organomercury used to preserve phage cocktails often destroyed them instead. Preparations could also be contaminated with exotoxins produced by the bacteria used to grow the phages. Finally, there have been problems in the past with inconsistency. The composition of a phage treatment may vary from batch to batch, with predictable effects on efficacy. Many physicians were less than happy with the results they got with phages. And when antibiotics were discovered, there was really no reason to continue to struggle with this form of therapy.

Things are different today, though. There are so many reasons why bacteriophage therapy makes sense. First, antibiotic resistance is increasingly becoming a problem. The utility of our antibiotics is dwindling, and the discovery of new antibiotics isn’t keeping pace. Antibiotics are static. But bacteriophages can evolve along with their bacterial prey. Instead of  struggling to identify new antibiotics, perhaps we could use phages and let natural selection do our work for us. If we’re lucky, maybe bacteriophages could replace some of the antibiotics we’re losing. In addition, we’re beginning to appreciate how important our microflora are. Wiping out our microbial ecosystem wholesale with antibiotics isn’t desirable, and it can increase susceptibility to pathogens like C. difficile. Bacteriophages, because they target only specific types of bacteria, might get around this problem–killing the problematic bacteria, but leaving everything else intact. Mixtures of phage could potentially be tailored to a person’s specific infection.

One of the reasons that phage therapy has been slow to catch on in the U.S. is that it has been primarily practiced in Eastern Europe and the Soviet Union. Today, phage therapy is routinely being used in Russia and the Republic of Georgia. But over the years, much of the work done was not published in English, so scientists in the West were unaware of it. In addition, many studies didn’t meet the standards that western scientists require. And, of course, getting approval to use a new therapy in the clinic is tough. As a result, companies have been wary of trying out phage therapy in humans and have been using it in different settings instead. Phages targeted to Listeria, a food-borne pathogen, have been approved by the FDA to help sterilize processed foods. Other phage mixtures have been approved to protect crops against pathogens. And more phage treatments are in the works.

Baby steps toward human treatments are being made, though. In the U.S., several safety studies in humans have shown promising results. And the first randomized controlled trial in the West was recently performed by Biocontrol Limited. It targeted adult patients with chronic ear infections caused by antibiotic resistant Pseudomonas aeruginosa; a bacteriophage solution was swabbed on infected ears. The researchers involved reported outcomes that were better than those achieved with a placebo, which is promising! As we have begun to appreciate the ecosystem in our guts, some researchers have proposed that bacteriophage therapy could help us perform more subtle manipulations than the ones to which we’re accustomed–by introducing certain phage, perhaps we could promote the biosynthesis of nutrients or the breakdown of parts of our diet.

Phage therapy faces some of the same major challenges that antibiotics do. Bacteria can develop resistance to bacteriophages. And a given phage can only target a relatively narrow range of bacteria. For these reasons, often a mixture of phage are administered to a patient. In terms of obtaining regulatory approval, this can be tricky, however. Although treating people with multiple phages does prolong the time until resistant bacteria arise, resistance may be inevitable. Therefore, researchers have been throwing around ideas like combining phage and antibiotic treatments (which seems to work especially well), cycling different phage mixtures, or engineering phage that can circumvent mechanisms of resistance.

Delivering the phage to where they need to go can also be tough. They have to spread from the site of application, and they also have to avoid being cleared from the bloodstream. For that reason, researchers have been focusing on infections that are localized (like ear infections and wounds). Over time, it may be possible to engineer delivery systems that will enable phage treatments to be used for more systemic infections. Some researchers have even shown that specially-engineered bacteriophages have the potential to break down biofilms, a gooey layer of protection that bacteria can hide behind.

Bacteriophage therapy may not be ready for primetime yet, but great strides have been made in the past few years. I’m really looking forward to seeing where this alternative type of treatment is going to go!

Chronic Lyme disease: it sounds so legit

lyme-disease-rashA lot of us are plagued with vague but unpleasant symptoms like fatigue, a sore throat, trouble sleeping, headaches, depression, or back pain. This is obviously no fun, and people want solutions. In recent years, an increasing number of people with these problems have been diagnosed with chronic Lyme disease. And they have found that getting treatment is not easy. Patients have fought their insurance carriers, trying to get them to pay for the long courses of antibiotics that they have prescribed. Lawmakers have tried to intervene: legislation to mandate coverage for chronic Lyme disease treatments has been proposed in Maryland, Pennsylvania, Connecticut, Massachusetts, Minnesota, New Hampshire, Vermont, Maine, and New York. Connecticut’s attorney general even brought an antitrust suit against the Infectious Diseases Society of America, because it refused to include extended antibiotic therapy for persistent infection in its guidelines (giving cover to insurance companies that wanted to reject claims). This is an awful but familiar story, right? Insurance carriers trying to push costs onto their customers is nothing new. But in this case, the insurance companies are probably in the right for once.

Lyme disease, of course, is real. We all know to beware of ticks when we are walking in the woods, and to watch out for the bull’s eye rash around a bite that means Lyme disease. The disease is caused by a bacterium called Borellia burgdorferi that ticks carry. A course of antibiotics, and afterwards all is fine. But what if you miss the early signs and symptoms and don’t treated? You might go on to develop a chronic infection, complete with early onset arthritis, heart problems, and Bell’s palsy. Lately, though, the concept of chronic infection has broadened. Some doctors are diagnosing patients with chronic lyme disease even if they don’t remember ever having a tick bite or a bull’s eye rash. And even if there are no signs of infection specific to Lyme disease. What is going on?

The waters around Lyme disease started to muddy in the 1980s, when a group of researchers reported that you could get Lyme disease, receive prompt treatment, and still go on to develop chronic infection. The worst thing was, these patients had no antibodies to B. burgdorferi! That means that if you tested these patients for Lyme disease, they would be seronegative–it would look like everything was fine. Although later research showed that serological tests actually were reliable for diagnosing late-stage Lyme disease, the ball was already rolling.

A relatively small number of doctors are very active in diagnosing chronic Lyme disease. They call themselves “Lyme literate.” Many of them are members of the International Lyme and Associated Diseases Society, and a number have been sanctioned, reprimanded, or even convicted of charges related to fraud and malpractice. Since they argue that you can have a longterm infection and still remain seronegative for infection, they can diagnose pretty much anyone with chronic Lyme disease. If you visit one of these doctors complaining of relatively vague and non-specific symptoms, such as pain, fatigue, or neurocognitive issues, you will probably leave with the diagnosis. Sometimes it’s even backed up by tests performed by laboratories that specialize in providing positive results by using methods that don’t adhere to official guidelines.

What are the drawbacks of getting treated for chronic Lyme disease when you don’t have it? First, of course, someone is taking your money to treat you for something you don’t have. And these treatments can get expensive! Second, and probably worse, the treatments have side effects. Serious ones. Some doctors have been infecting patients with malaria, which they say will get kill B. burgdorferi. Others are injecting them with bismuth, and sometimes the results aren’t pretty. The lucky patient will get a long course of antibiotics, but  even this is serious business. Allergic reactions to the antibiotics, infections at the site of the I.V., and other complications have resulted in the death of patients. And in one unpublished study, a fifth of the patients who received this type of treatment had serious adverse events, usually related to the I.V..

People plagued with symptoms that no one can nail down are desperate for answers. Many visit doctor after doctor with no success. Then, they read a compelling story like this one and wonder if being treated for chronic Lyme disease could transform their lives too. Or they see a documentary like Under our Skin and become convinced that Lyme disease is responsible for their symptoms. When most of us want to learn more about a topic, our first stop is the Internet. Unfortunately, many of the activist groups lobbying on behalf of chronic Lyme disease have bland names and professional-looking websites that lead people to think they are sources of unbiased information, like the Lyme Research Alliance, the Lyme Disease Association, and the California Lyme Disease Association.

One study of patients seeking help for chronic Lyme Disease found that many suffered from psychiatric problems–which probably explained their symptoms. Psychiatric problems can be treated, but most of us don’t want to hear that we have them. It’s more appealing to think a course of antibiotics is the answer. Even the suggestion of a cure is often enough to make chronic Lyme disease patients feel better; one randomized controlled trial found that roughly 40% of the patients assigned a placebo improved. Just the belief that they’ve finally identified their problem and are getting help makes a difference. In the end, chronic Lyme disease is just another example of the way we attempt to transform psychological problems into something more manageable, something with a clear external cause and a straightforward solution. It’s a shame that we can’t provide this kind of relief without made-up diseases and harmful, unnecessary treatments. If it weren’t unethical to deceive patients, this seems like a case where prescribing sugar pills could make a big difference!

Vaccines and Autism: A crisis of legitimacy?

photo-injectionWhat do you do when you are part of a movement, you pour your heart and soul into it, and then things start to fall apart? Like members of a religious cult the day after the world doesn’t end, eventually you have to move on. But it must be really tough. In the same way, it seems to many of us as though the vaccines-cause-autism groups are going to have to grapple with the hard truth soon. But are we silly to think that?

Years ago, organizations like the National Vaccine Information Center and SafeMinds put forth a hypothesis: that vaccines cause autism. They called for the research community to test it. Now, study after study after study after study after study after study has come out debunking any link between vaccines and autism. One of the biggest leaders in the anti-vaccine movement, Andrew Wakefield, has been disbarred and disgraced, having kicked the whole debacle off with a fraudulent scientific article in a high profile journal. Other medical experts who have lent support to anti-vaccine groups, like Dr. Mark Geier and his son David Geier,  have met similar fates. Not surprisingly, given the mountain of evidence against a link between vaccines and autism, the access of anti-vaccine groups to policy makers appears to be waning. And in the wake of falling vaccination rates, large measles epidemics have broken out in places like Swansea, demonstrating just why vaccines are so important. So what happens now? Will the members of anti-vaccine groups start to drift away? Or will the leadership abandon the vaccine-autism hypothesis and find something else to concentrate on, remain relevant somehow?

Last year, a really interesting article on exactly this question came out. It’s called The Legitimacy of Vaccine Critics: What is Left After the Autism Hypothesis? and it appeared in Journal of Health Politics, Policy and Law. The author, Anna Kirkland, wanted to know how NVIC and its supporters were responding to all of these blows to the organization’s legitimacy. Her focus was on the leadership. Why would they continue to hang on to the vaccine-autism hypothesis when it meant losing the respect of the research and policy-making worlds? Kirkland attended the 2009 NVIC meeting and gathered data about who was there and what they believed.

Activist parents turned out in a big way, of course. Parents started groups like NVIC and have  kept them going. A specialized group of health professionals and researchers were also in attendance. Some of the health providers practiced alternative medicine; others practiced traditional western medicine, but opposed state-mandated vaccinations on libertarian grounds. You might be wondering what kind of researchers were there. Apparently, they typically publish in non-peer reviewed journals, occupying a sort of shadow research-world. Nevertheless, NVIC members feel these health professionals and researchers lend credibility to the group. Donors, of course, were important attendees. NVIC donors come from the left and the right side of the political world, and many are big movers and shakers in the world of political fundraising. Finally, there was the media. Mothering magazine and the Huffington Post are apparently two sympathetic news sources for parents who choose not to vaccinate their kids. Kirkland argues that all of these constituents have joined together to create a world of internal legitimacy. The NVIC leadership needn’t change course (and in fact, it would have a very difficult time doing so), because its constituents still believe they’re on the right track. What many of us view as major setbacks to the vaccine-autism hypothesis haven’t phased the members. Want an example? Check out the part of the SafeMinds website that deals with Vaccines and Autism. It’s as if the authors are not privy to any of the recent research–or with what scientific studies can and cannot show.

I’m convinced that it’s probably hopeless to try and change the minds of hard-core vaccine critics with data. But it seems as though many new parents are probably on the fence about vaccinating. They want to do what is best for their children, and they’re not sure what that is. They try to do due diligence and research their options. Have all the studies debunking the vaccine-autism connection affected THEIR views? Apparently, as recently as a few years ago one in four Americans believed that vaccines cause autism. And between 2003 and 2008, the percentage of parents who refused or delayed vaccines for their small children rose from 22% to 39%. So I’m not getting the feeling that the results of these studies are having the effect that we’d like. What we think of as blows to the vaccine-autism hypothesis are not finding purchase in the general public.

Have all these setbacks had any effect on the popularity of vaccine critic groups? Since NVIC and SafeMinds are nonprofits, I tried to find their annual reports. In the world of Public Health, it’s usually very easy to find an organization’s annual reports, stretching back for years. Not so for these groups. I was able to find a 2011 annual report for NVIC, but that’s all. I looked up both groups on GuideStar, which collects information about non-profits’ financials, and found a little more information there. It turns out that the loss of external legitimacy (i.e. the evaporation of respect from the research community and from the health policy world) doesn’t seem to be hurting these groups financially. In 2011, NVIC raised over $800,000–more than twice what it raised in 2009.  SafeMinds has also raised more and more money in recent years. Fundraising might not be the best measure of support for these groups, since a few big donors could contribute large amounts and mask trends in rank and file membership. But NVIC reported that in 2011, 1 million people viewed their homepage. It doesn’t seem like they are hurting for supporters.

gradusatodayAs a scientist, reading about the inner workings of the vaccine criticism movement was pretty sobering. A lot of researchers have diligently carried out research on vaccines and autism, laboring under the delusion that their data will change people’s minds. Kirkland’s research (and the ongoing epidemics of preventable infectious diseases that are taking place in the U.S. and other high income countries) makes it clear that this isn’t likely to happen anytime soon. Many vaccine critics call for research into various vaccine-autism hypotheses, but they do not trust any mainstream biomedical researchers to perform the studies. If your study is funded by the NIH (as most of our studies are), your results are not going to be taken seriously by members of these groups. I think initially it made sense to investigate the vaccine-autism hypothesis. But at this point, wasting time and money demonstrating the same thing over and over again, in hopes of converting people who will never be convinced, doesn’t seem like a good use of resources.

It seems that just as the vaccine critic movement has lost legitimacy in the eyes of the research world, we researchers have lost legitimacy in the eyes of many parents, at least when it comes to the science and epidemiology of vaccines. Groups like Generation Rescue seem to be doing a better job at communicating with nervous parents (check out their PSA above). I hope that in the future, we can find a way to bridge these two camps in order to prevent additional unnecessary outbreaks of infections like measles and mumps.

The zombies of Haiti: horror story or Hallmark Special?

zombieWoken by fireworks in the middle of the night for the umpteenth time this year, I remembered The Serpent and the Rainbow by Wade Davis. Davis, who studied zombification in Haiti, believed that turning people into zombies served as a sort of release valve for communities. Is there some jerk in the neighborhood making everyone’s life miserable? Get some zombie poison! After being zombified, the troublemaker will find himself on the other side of the island, where he will labor away on a zombie farm. Translated into Manhattan terms, if I turned my fireworks-loving neighbor into a zombie, he might wake up on the Lower East side and find himself slinging lattés at Starbucks for a few years until I released him, hopefully having learned a lesson. It seemed like a good solution. Then I stopped to wonder: what ABOUT all that zombie stuff in the The Serpent and the Rainbow? Could any of it possibly be true?

Here is the back story. Wade Davis is an anthropologist interested in ethnobotany. At Harvard, he studied under Richard Evans Schultes, rain forest explorer and photographer extraordinaire. Davis has spent his career exploring the medicinal plant use of indigenous cultures. Back in the early 1980s, Davis stumbled onto the world’s best dissertation project: go to Haiti and bring back some zombie poison. There had been rumors for years that zombification might have a pharmacological basis, and he wanted to figure out if there was any truth to this claim.

Studying zombification is not easy, especially since it’s against the law in Haiti (Article 246 of the Penal Code). But Wade managed to collect zombie poison from four different voodoo sorcerers on the island, and found a few consistent ingredients. One of them was puffer fish, which contains tetrodotoxins, neurotoxins that can cause a temporary death-like state. So, potentially, an irate neighborhood or unhappy family member could dose someone with zombie poison, and everyone would think they were dead. After the funeral and the burial–in the dead of night–the zombie-maker would dig up the victim, before they woke from their tetrodotoxin-induced sleep. At that point, the poor slob would be drugged with still other concoctions, to keep them in a compliant, zombie-like state.

Of course a claim like this is bound to draw a lot of attention. Other scientists had many questions. Were the biochemical tests done in a way that could distinguish between active and inactive forms of the puffer fish poison? Were the levels of tetrodotoxin sufficient to actually poison someone? Wasn’t it wrong for Wade to help dig up the remains of a recently buried child in order to get the materials for the zombie poison? (That was part of the book.) Words were said. Critics C.Y. Kao and T. Yasumoto, who found only insignificant traces of tetrodotoxin in the samples Wade sent them, said: “We hold firmly that science done without a moral and ethical foundation can never be more than a mockery of science. And that, in our view, is what [Davis] and [his collaborators] really are.” And Davis accused them of “old-fashioned jealousy.”

In 1997, what has got to be the most interesting paper ever to grace the pages of the Lancet appeared: Clinical findings in three cases of zombification. First, the authors estimated that roughly 1,000 cases of zombification are reported in Haiti every year. I am not making this up. Then, they moved on to their findings. They had identified three Haitians whom family members said were zombies–that is, these people had fallen ill and been buried by their families, only to reappear months or years later, wandering around in a zombie-like state. The researchers listened to the families’ stories, interviewed the putative zombies, performed physical exams, and ended by performing DNA tests. The first woman they examined appeared to have catatonic schizophrenia, and her appearance was quite different than that evident in before-death photos. No DNA tests were performed in her case. The second zombie was a young man in his 20s, said to have been turned into a zombie by a jealous uncle (who was sentenced to life imprisonment for this crime). The researchers diagnosed him with cognitive impairment and epilepsy; DNA tests demonstrated that he was not related to the couple who was convinced he was their son. The last case involved a young woman who had died and then disappeared for over ten years before being found. After leading researchers to the area where she said she had been kept as a zombie for all that time, the villagers there recognized her as a local who had gone missing. And DNA tests showed she was not related to the family who had claimed her as their zombie daughter. Like the young man, this woman appeared to have some sort of cognitive impairment, possibly due to fetal alcohol syndrome.

Based on this case series, the authors concluded that what was probably going on was less mysterious and exciting than the widespread creation of zombies with voodoo poison. The zombies they studied appeared to be young people with psychiatric disorders who were adopted by bereaved families. Mistaken identity, rather than voodoo, seemed to be the culprit. These scientists also pointed out that it seems a little incredible that secret zombie farms could go undetected for long in a place as crowded as Haiti.

So, yes, science kind of ruined a great zombie story. But even if zombies aren’t being created using voodoo poison, something fascinating is going on here. The zombie myth persists in Haiti for a reason. The three people studied in the Lancet article (and others who have been identified over the years) acquiesced to living with strangers who considered them zombies. That’s pretty interesting in its own right! And their adopted families chose to overlook the many differences between their new zombie children and their deceased loved ones. The zombies were filling a need. It makes you wonder if something that began as a horror story could actually be a heartwarming (if bizarre) tale about people opening their homes and hearts to some of society’s most vulnerable individuals. It seems like the Lancet research supports a kinder, gentler take on zombies.