Tag Archives: malaria

Seven Stories Of Science Gone Wrong

What, with all the attacks on science and scientist these days, we may not want to be focusing on those times when science goes off the rails and makes a huge mess of things. But, science at its best and scientists at their best, will never shy away from such things.

Dr. Paul Offit just wrote a book called Pandora’s Lab: Seven Stories of Science Gone Wrong, which not about an evil black dog that escaped from a box, but rather, seven instances when the march of scientific progress headed off a cliff rather than in the desired direction. People died. Many people died. Other bad things happened.

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Note: I interviewed Paul Offit about his book on Atheist Talk Radio. This interview will be aired on Sunday, May 28th, and will be available as a podcast. It should be HERE.
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Readers will have different reactions to, and ways to relate to, each of the seven different stories, because they are far flung and cover a great deal of time, diverse social settings, and a wide range of scientific endeavors. Some readers will get mad because he talks about DDT and Rachel Carson, though I assure you his argument is mostly reasonable (I did disagree with some parts). All readers will be amazed at the poppy plant and all it can do and has done, and astonished at the immense apparent ignorance displayed by that plant’s exploiters, from back in the early 19th century to, well, yesterday. Those interested in race and racism, the use of poison gas to kill people, will find things you didn’t know in Offit’s carefully researched histories. Also, don’t forget to take your vitamins. Or, maybe, forget to take your vitamins.

The chapter “The Great Margarine Mistake” is a great example of the very commonly screwed up interface between food science, food production and marketing, and the shaping of food preference among regular people. You know, that thing where “They tell us not to drink coffee. Then they tell us to drink coffee. They don’t know nothin'”

My biggest disagreement with Paul is over malaria. He did not incorporate an often overlooked fact about the disease into his discussion, and had he done so, may have written a somewhat different chapter. Briefly, in zones where there are two wet seasons (or one long wet season and a very short dry season) there has never really been success in curtailing malaria. In zones where there is a very long dry season but it is wet enough for part of the year for the mosquito that carries malaria to exist at least most years, malaria is relatively easy to beat down using a wide range of techniques, no one of which is supreme. So, for example, today, the distribution of malaria in South Africa, where it is not actually that common (thousands of cases in a normal year among tens of millions of people) is determined mainly by how wet the eastern wet season is, integrated with the movement into that area of people, usually refugees, who are a) infected and b) not getting medical treatment. (See this.)

Malaria was wiped out in country after country prior to the use of DDT, then the DDT came in and helped a great deal, in those relatively dry countries. But the wet countries, not so much. Indeed, in a place like Zaire, there are absolutely no reliable statistics on how common Malaria is or ever was over most of the country, but when I lived there in the 1980s, it was as common as the common cold in New Jersey, and DDT was theoretically in use. (That is a second correlation with causation: the wetter the equatorial country, the less we actually know about disease. I recall leaving the deep rain forest to visit the “city” to get hold of a few courses of leprosy medicine for a handful of people who visited our clinic who had it, where I had dinner with a guy from the UN who was on his victory lap for having wiped out leprosy in Africa.)

In some ways, Offit’s final chapter is the most interesting, the eighth chapter (combined with the Epilog) in which he does two things. One is to identify the kind of reasoning mistake, or methodological mistake, each of his seven examples exemplifies. Such as failure to pay attention to the data, or failure to pay attention to the man behind the curtain. The other is to go quickly through what may end up being similar stories of science gone wrong just starting to brew today or in recent decades, such as the long term unintended effects of widespread use of antibiotics.

A question that Offit’s book raises, indirectly, is this: When a Pandora-like box opens and some sort of monster creeps out, why did the box open to begin with? Sometimes it is jostled open, like in the case of unintended negative outcomes from the use of antibiotics. Sometimes it is opened because someone can’t resist the treasures that may be inside. Sometimes it is opened because science is an open process and must always seek knowledge etc. etc. I wonder if the recent development of an engineered polio virus (three instances), or the Spanish Flu, is an example of such. Sometimes it is opened because of (Godwin Warning!) HITLER. Seriously.

I don’t know what knowing these reasons gets us, but one possibility is this: when we find ignorance as a root cause of calamity, perhaps an appreciation of knowledge is gained. That is certainly the lesson of Offit’s review of the products of opium, their invention, intensification, deployment, and use. Apparently addiction was simply not understood at all until fairly recently, and that lack of understanding caused science, medical technology, and medical practice to do the exactly wrong thing over and over again.

And of course, lobotomies. The invention of the latter method of doing this useless and horrible procedure is something that, if put in a movie as a plot element, would kill the movie because it is not possible to suspend disbelief to the degree necessary to stay seated in the theater.

Pandora’s Lab: Seven Stories of Science Gone Wrong is a great read and a necessary addition to the bookshelf of any practicing skeptic or science enthusiast.

Paul Offit, who is a pediatrician and the inventor of a rotavirus vaccine (see this for an interesting podcast on a related topic), is the Maurice R. Hilleman Professor of Vaccinology and Professor of Pediatrics at the Perelman School of Medicine, University of Pennsylvania. He is also chief of Infectious Diseases and director of Vaccine Education at the Children’s Hospital of Philadelphia.

Aside from Pandra’s Lab, he also wrote Do You Believe in Magic?: Vitamins, Supplements, and All Things Natural: A Look Behind the Curtain, Deadly Choices: How the Anti-Vaccine Movement Threatens Us All, and Bad Faith: When Religious Belief Undermines Modern Medicine.

Has #Ebola Death Toll Surpassed Malaria in West Africa?

In the earlier days of the West African Ebola outbreak, it was not uncommon to hear people note that we should not panic about Ebola because, after all, far more people are killed from Malaria than Ebola. This is of course an irrelevant argument. That is like telling a person who has lost their family in a tragic airplane accident that it isn’t so bad because, after all, far more people die in car crashes than aircraft crashes. For example, on August 5th, James Bell write in the Guardian, in a piece called Concerned about Ebola? Youโ€™re worrying about the wrong disease:

Since the Ebola outbreak began in February, around 300,000 people have died from malaria, while tuberculosis has likely claimed over 600,000 lives. Ebola might have our attention, but itโ€™s not even close to being the biggest problem in Africa right now. Even Lassa fever, which shares many of the terrifying symptoms of Ebola (including bleeding from the eyelids), kills many more than Ebola โ€“ and frequently finds its way to the US.

I’m not picking on James Bell here. A lot of people said things like this, and the facts are true, though as I said, there is almost always (actually, in exactly N-1 scenarios within a given domain of scenarios) an argument that goes like this, and it really isn’t particularly relevant unless one is tasked with dividing up a fixed set of resources that will be used for a fixed set of problems. Resources rarely come that way and problems are rarely solved that way. As I pointed out earlier, consider the thought experiment where you have $10,000,000 that you want to give to either developing an Ebola vaccine, or a Malaria vaccine. Since billions have been spent on developing a Malaria vaccine and there still isn’t one, your donation would be a drop in the bucket. Retrospectively, it would be equivalent to something like the combined costs of couriers and mail by researchers working on a Malaria vaccine over the last few decades. Or the cost of coffee and donuts in the break room. Or conference travel fees. Or something like that. The point is, a bunch of millions of dollars might actually produce an Ebola vaccine given the starting point we have now, or at least, move us a good deal in that direction.

But now, we can ask if Ebola in the countries that are heavily affected right now is still “minor” compared to Malaria.

This is a matter of numbers and the numbers are hard to come by. James Bell notes that between February and July, inclusively, there had been over 300,000 malaria deaths, I assume world wide. So the comparison is not really relevant; we should be looking at what is happening specifically in, for instance, Liberia, Guinea, and Sierra Leone (or the three combined perhaps). Comparing world wide figures to a regional outbreak is a bit like reducing the Malaria death rate by shifting from numbers from countries that have endemic Malaria to include the global population.

It is hard to know how many people die of malaria every year, and the quality of the data varies considerably from country to country. A fairly recent study (here’s a discussion of it) suggests that an older estimate of 600,000 deaths per year should be doubles to 1,200,000 deaths per years. Having worked and lived in a region with some of the worst malaria (measured numerous ways) for several years, I can easily accept a doubling of numbers. If we assume that 1.2 million is right, by the way, Bell’s number of 300,000 is actually conservative.

Using data from that malaria study and WHO’s Ebola data, we can make some comparisons. I’m including all the information so you can check my work.

Here we have data from Liberia, Guinea, and Sierra Leone. The population number and malaria deaths per year are both from the aforementioned study and pertain to 2012. Then I divided malaria deaths per year by 12 to get a monthly value. I’m more comfortable working in months than years because an Ebola outbreak is normally short lived, and the number of deaths changes dramatically from month to month.

Following this we have the total number of Ebola deaths per country (summed in the right hand column as are the above mentioned data) and the approximate number of months of the outbreak. Then, the total deaths divided by the number of months. This constitutes a low-ball estimate of deaths per month from Ebola for the given expanding outbreak. Here we can see that in the comparison between Malaria and Ebola, it is not clear that one is a greater threat than the other (142:92, 49:67, 145:144).

Then we have the August-only monthly number of deaths. Here we dee that Ebola is huge compared to Malaria. So, back when people were saying “Malaria is worse,” in late July and early August, Ebola was starting to prove them wrong.

The last two numbers are calculated for all three countries combined. Here we are going out on a limb, and it is better statistically to crawl out on a thicker limb than a thinner limb. I made some estimates here, and those numbers conform to what is being talked about by WHO and others. If Ebola continues to spread at its current rate the daily number of new cases could be between 150 and 300 by the beginning of January. I state these as low vs high estimates, but actually, they are both conservative. Multiplying this by 30 days in a month, and dividing by 2 to approximate the ca 50% mortality rate, we have conservative numbers for Ebola that leave Malaria in the dust. Even if the doubling of estimated Malaria death rates should be doubled again, Ebola will be a bigger factor than Malaria.

Liberia Guinea Sierra Leone Total
Population 3,954,977 10,068,721 5,696,471 19,720,169
Malaria Deaths Per Year 1706 586 1734 4,026
Malaria Deaths Per Month 142 49 145 336
Ebola Deaths Total 508 400 461 1,369
Months of outbreak 6 6 3
Monthly average Ebola deaths 92 67 144 303
August Ebola Deaths 644 148 224 1,016
Estimated Janurary Ebola Deaths (low) 4,500
Estimated Janurary Ebola Deaths (high) 9,000

So that is why we should stop saying that Ebola is not Malaria, so relax about Ebola.

More on Ebola:

Why isn’t there a malaria vaccine, and could there be one soon?

There are several reasons why there is no vaccine for malaria, but the thing you might want to know is that malaria is not a virus, and it is not even a bacterium. It’s a protist. Generally speaking, there are not really vaccines for such organisms. One metastudy that looked specifically at Malaria had this to report:

Continue reading Why isn’t there a malaria vaccine, and could there be one soon?

Does drinking beer increase your attractiveness …. to mosquitoes?

ResearchBlogging.orgThe anopheles mosquito, Anopheles gambiae, is the primary vector for human malaria. Mosquitoes in general, the A. gambiae included, find their prey by tracking body odor exuded from the breath and skin. Apparently, the composition of body odor determines A. gambiae‘s preference for one individual over another. It has been known for some time now that A. gambiae preferentially seek out and draw blood from pregnant women (Linsay et al 2000; Ansell et al 2002; Himeidan, Elbashir and Adam 2004), preferring pregnant over none pregnant women at about a 2:1 ratio.

i-3313e722b5aa8b91154aec92dd249db4-AnophelesGambiaemosquito.jpg

Continue reading Does drinking beer increase your attractiveness …. to mosquitoes?