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World AIDS Day – Science & Pseudoscience of AIDS Michael Edmonds Nov 30

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In the early 1980s, the emergence of a previously unknown and fatal disease, raised concern amongst medical professions and fear in the general population. Those suffering from this new disease presented with a range of opportunistic infections, including rare forms of pneumonia and cancer – suggesting the cause was a failing immune system.

Thirty years on, we now refer to this disease (or more correctly syndrome) as AIDS (Acquired Immune Deficiency Syndrome) and understand it is caused by HIV (the Human Immunodeficiency Virus).

Much has changed over those thirty years – socially, politically and scientifically. Here, I will focus on the latter describing how fight to combat AIDS and HIV has resulted some of the most brilliant science, and also some of the most appalling pseudoscience.

Fighting a disease requires learning as much as you can about it, in particular being able to isolate the cause. In 1984, this piece of the puzzle was solved by two teams, one in the US and one in France – the cause of this new disease was a retrovirus; named the Lymphadenopathy Associated Virus (LAV) by Luc Montagnier’s team at the Pasteur Institute in France, and HTLV –III by Robert Gallo’s team at the National Cancer Institute, the virus would eventually be known as HIV. On both sides of the Atlantic there were often bitter debates about whose contribution to the discovery of HIV was greatest, which was exacerbated in 2008, when Montagnier, but not Gallo, was awarded the 2008 Nobel prize in physiology and medicine.

The identification of the cause of AIDS, opened the door to a number of research opportunities including the development of a test to detect HIV, drugs to combat HIV and vaccines. One of these was achieved within a year, another required over a decade of research before significant progress was made, and the third has yet to be achieved.

By 1985, a blood test to detect for HIV antibodies was developed and immediately used to screen blood banks. The ability to test patients for HIV also allowed medical professionals to gather more data of the disease, however, without appropriate treatments or a vaccine the death rate from AIDS related conditions continued to climb.

In 1987, the first antiretroviral drug, AZT, was approved by the Federal Drug Administration (FDA) for use in the treatment of HIV infection and AIDS. A fairly blunt weapon in the treatment of HIV and AIDS, many of those given AZT experienced severe side effects, a fact which was later twisted by proponents of pseudoscience to suggest that these treatments actually “caused” AIDS. 1987 also saw the political group ACT UP successfully lobby the FDA to speed up drug approvals.

Over time, modification of AZT dosage lead to improved treatments and in 1990 it was approved for treatment in pediatric AIDS. However, the effects were not great and in 1990 the median time to death after diagnosis of AIDS was one year. It was not until 1995 and the development of the first HIV protease inhibitor, saquinavir, that more effective treatments of HIV began to emerge.

The development of HIV protease inhibitors proved to be a significant turning point in the war of AIDS. By effectively “jamming” the protease enzyme in its’ production of the proteins required for HIV to replicate it slowed the ability of HIV to infect new cells. Saquinavir, was quickly followed by other protease inhibitors and in 1996, nevirapine the first of another family of drugs, the Non Nucleoside Reverse Transcriptase Inhibitors (NNRTI) emerged.  NNRTI’s, like AZT, interfere with the copying (or transcription) of viral genetic material into the host cells DNA, however, unlike AZT their structure is not based on the naturally occurring nucleotides in DNA.

Now having a range of drugs with which to treat HIV, doctors experimented with varying combinations and HAART (Highly Active Anti-Retroviral Therapy) became the standard treatment whereby patients were treated with several drugs simultaneously. As these treatments were perfected into the 21st century, deaths from AIDS began to decrease, and life expectancy of those with HIV began to lengthen.

The benefits of having multiple drugs to treat HIV are two-fold. Different types of drugs target different pathways that the virus uses to reproduce in the body. The more pathways that can be disrupted the less chance the virus has to reproduce. Also, HIV has the ability to mutate allowing it to become resistant to a specific drug – should this occur, the ability to switch to a new combination of drugs means that HIV replication can still be suppressed.

The effectiveness of the drugs developed in the 1990s lead to somewhat of a reduction in interest by drug companies to develop new drugs to treat HIV moving into the 21st century, however, some notable achievements included the development of fusion and integrase inhibitors. The first fusion inhibitor, Enfuvirtide, was approved by the FDA in 2003 and works by blocking the ability of HIV to fuse with cells and infect them. Raltegravir, the first integrase inhibitor was approved for use in 2007, and works by blocking the enzyme which integrates viral material into the host cells DNA. Incorporation of these drugs into the armamentarium available to today’s medical professional has further improved the outcome for those infected with HIV, with life expectancies expanding beyond several decades.

Although modern treatments of HIV have extended life expectancy and can reduce viral load to undetectable levels, this should not be accompanied by complacency. HIV still requires careful management – any break from the daily drug regimen can allow the virus the opportunity to develop resistance. Even after 30 years there is no cure, just careful management HIV’s replication. The old adage that prevention is better than cure an appropriate one.

 

AIDS related Pseudoscience

Like many other areas of science, HIV research has attracted its’ fair share of pseudoscientific beliefs. One of the most prominent are claims that AIDS is not caused by HIV. One of the key proponents of this argument is Peter Duesberg whose book “Inventing the AIDS Virus” claims that HIV is not the causative agent. Instead, his claims tend to be based on the suggestion that it is a “lifestyle” disease caused by a range of factors such as drug use (including anti-retrovirals), poor nutrition and poor sanitation. Such claims have been widely dispelled by the scientific community as they do not match the evidence. Indeed my impression of Duesberg’s book is that it has a moralistic rather than scientific undertone.

Based on the claims of Dueberg and other opponents of retroviral therapies, President Mbeki of South Africa delayed the use of these therapies in South Africa, in favour of traditional “remedies” no doubt resulting in hundreds of thousands of unnecessary infections and deaths.

Over the past 30 years homeopaths have also made regular claims that they hold the answer to curing AIDS, however, no evidence has been presented. Similarly claims that HIV can be treated or cured through nutrition have never been proven. And where such alternative treatments are used to replace conventional treatments, the typical consequences are a much shorter lifespan.

Conspiracy “theories” occasionally arise around the origin of HIV, including the suggestion that it was engineered to kill off one section of the population, for example African Americans or homosexuals. Given the nascent state of the sciences that would have been required to do this in the 1980s’ such ideas would be almost laughable if they weren’t so disturbing.

Homeopathy takes another hit Michael Edmonds Nov 11

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On Friday 31st of October Dr Siouxsie Wiles from Sciblogs very own Infectious Thoughts blog gave an excellent interview of Breakfast TV explaining why homeopathy isn’t an appropriate treatment for ebola (or anything else).

Now Vicki Hyde from NZSkeptics has presented a thorough explanation of why homeopathy is not a valid medical treatment on CTV, including a demonstration of how homeopathy dilutions “work”.

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This is great because I think the best way to discourage people from using homeopathic remedies is to explain to them what it is.

Homeopathy not the solution for Ebola (or anything else) Michael Edmonds Oct 30

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A petition calling for the World Health Organisation (WHO) to “test and distribute homeopathy as quickly as possible to contain the (Ebola) outbreaks” is unlikely to gain much traction, given that the WHO, in August 2009, made statements indicating that homeopathy was not an effective treatment for diseases such as tuberculosis, malaria, diarrhoea or HIV infection.

Unfortunately, Green MP Steffan Browning does not seem to have been aware of this when he signed an on-line petition, asking the WHO to consider treating Ebola with homeopathy. Since this revelation the Green party has distanced themselves these comments with Greens co-leader Russell Norman stating that ”There are many New Zealanders who use homeopathy but I think even they would say it’s not the right thing to use for Ebola. It’s not something we support and it’s not Green Party Policy.” Mr Browning has also back pedalled his position suggesting it was “unwise” to sign the petition. However, it is noticeable that both Mr Browning and Dr Norman have been very careful in how they have worded their response so as not to offend those who believe in homeopathy.

The petition demonstrates a naivety about medicine and homeopathy with the petitioners requesting

We call on those within WHO in positions of authority and influence to:

1. Look at homeopathy’s record in the treatment and prevention of serious epidemic disease

2. Engage with qualified representatives from the homeopathic profession to formally identify the best-indicated remedies

3. Test those remedies to determine which are best for the treatment and prevention of Ebola

4. Obtain supplies of those remedies from waiting and concerned homeopathic pharmacies

5. Bring the outbreaks under control by distributing these remedies as quickly as possible throughout the affected areas.

Finally, please end the suffering of those in the Ebola crisis by using the tried and proven homeopathic option.

 

Repeated studies of homeopathy have already demonstrated that when it is tested properly it has no noticeable effect beyond the placebo effect, and when it is used instead of effective medicines it can put people’s lives at risk. Many of those who accept homeopathy may also be doing so under the misapprehension that it is a herbal medicine. It is not.

Homeopathy is based on a series of nonsensical suppositions. First, that a disease can be treated by using a substances that causes the same symptoms. Second, that by diluting this substance to the extent that none of the existing material remains, it creates a cure, and the more you dilute it the more effective it is as a treatment. Third, that between dilutions the striking (succussing) of the container in a certain way somehow transfers curative properties to the water.

Homeopathy arose 200 years ago, when medicine was still developing and was steeped in myth rather than science. At a time when doctors prescribed toxic concoctions such as mercury and arsenic salts and regularly bled patients, a magical bottle of water may have indeed been your best option for survival. However, modern medicine has now advanced to treat many diseases, diseases which homeopathy has not managed to treat in spite of having 200 years to do so.  To now suggest that homeopathy is an appropriate way to combat Ebola is naive and dangerous.

Pain, Pus & Poison – a fascinating series covering the development of modern medicine Michael Edmonds Oct 28

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I’ve always been fascinated by the evolution of modern medicine, particularly the development of modern pharmaceuticals, so I was looking forward to catching “Pain, Pus & Poison – The Search For Modern Medicine” on Sky TV, however, managed to miss the first episode. Luckily I discovered the episodes are also available on Youtube

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The first episode covers the development of some of the drugs that have changed history – from ether and nitrous oxide for pain free surgery, aspirin for treating pain and fever, to some of the less spectacular developments such as heroin and chloral hydrate (the active ingredient of a Mickey Finn).

The first episode was an fascinating mix of science, history, and self experimentation, as producer, Michael Mosley demonstrated the effects of drugs including nitrous oxide and sodium pentothal (definitely don’t try this at home).

I look forward to watch the next few episodes.

Gluten Free & Pseudoscience Michael Edmonds Aug 10

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There is little doubt that some people have an intolerance to gluten and that a gluten free diet is an appropriate way to address this. However, the gluten free diet is also associated with pseudoscience in terms of what it can achieve and how it is diagnosed.

Take, for example, the recent news that tennis player, Novak Djokovic, has embraced a gluten free diet on the advice of his nutritionist. According to a recent article by Dr Joe Schwarcz, Djokovic was diagnosed as follows:

Djokovic’s “nutritionist” asked him to stretch out his right arm while placing his left hand on his stomach. He then pushed down on the tennis champion’s right arm and told him to resist the pressure, which he was able to do. Next, Djokovic was asked to hold a slice of bread against his stomach with his left hand while the nutritionist again tried to push down on his outstretched right arm. This time, he was able to push it down easily. The demonstration, Djokovic was told, showed that he was sensitive to gluten, which is why he had suffered so many mid-match collapses in his career.

Some readers will be aware of this “applied kinesiology” approach where the apparent “weakness” is the result of adjusting the angle of the pressure applied by the practitioner, not by the presence of a slice a bread. Hardly an appropriate method for diagnosing any disease or disorder.

 

 

Taking an Experimental Approach to Weight Loss Michael Edmonds Aug 03

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I need to lose some weight.

The was the conclusion I came to on a Friday night just over a week ago when my bathroom scales told me I weighed 92.2 kg, which according to a BMI calculation for my height and weight puts me into the “overweight” category. Not the best place for someone who has a family history of heart disease and who is already exhibiting early signs of osteoarthritis.

Of course, I have known this for a while – prior to the Christchurch quakes I weighed around 85 kg, however, when the quakes stuck and took out my gym (and most of the others around Christchurch) for 6 months my weight increased, helped along with the comfort food consumed during this time. Even though I still go to the gym 3-4 times a week, I’ve never lost the weight I gained.  I’ve been meaning to do something about it for a while now, but on Friday a convergence of several factors helped me resolve to explore how to lose some weight.

One of these factors was watching a documentary by Michael Mosley called Eat Fast and Live Longer. In the documentary Dr Mosley explored the use of fasting to improve health and encourage weight loss. Various approaches to fasting were explored but by the end of the documentary Dr Mosley had settled on a 5:2 approach to dieting, whereby calorie intake was restricted to 600* calories a day for two days of a week, while one eats normally for the other 5 days. A book has now been produced based on this documentary outlining this dietary approach.

* that is 600 calories for men, 500 calories for women

So on Saturday, I decided to try to see what this fasting approach would be like. Porridge with half a banana and skim milk  for breakfast consumed 150 calories. Finding myself hungry by lunch a sandwich with soup took out 300 of my remaining allowance of calories. By evening I was hungry for more than the remaining 150 calories so had a reasonably healthy chicken and vegetable dinner of 386 calories.

So fasting wasn’t as easy as I thought, however, I had achieved a day of relatively low calorific intake. If I could sustain this surely I would lose weight? I decided to turn this into an experiment – if I continued on a restricted calorie diet would I lose weight? The short answer is yes.

In order to track my food intake, I decided to use an iPad app called MyFitnessPal which allows you to calculate your calorie intake using a database containing information on the nutritional content of a wide range of foods. Since last Saturday morning my calorific intake (measured in kJ) has been as follows:

 


calories

The orange line is the number of kJ which the MyFitnessPal determined that I should be able to get moderate sustained weight loss with. The blue points indicate my calorific intake for each day (in kJ) with large increase on the 2nd of August due to a “cheat day” where I ate what I felt like, including some chocolate brownie ice cream. Some well known diets recommend a cheat day once a week as a treat. As well as relaxing for a day I was interested in seeing what effect it had on my weight.

weight

Over the week I have had a significant weight loss. However, most interesting to me is what happened at the beginning when I went from a day (Friday) of poor eating choices to a restricted calorie diet. The drop in weight was quite substantial. Also, the morning after my “cheat day” my weight jumped by almost 1 kg. It is an interesting effect which I’m curious to explore further.

In conclusion, it would appear a restricted calorie diet is working for me. It will be interesting to explore further how varying my calorie intake affects the weight loss, and whether my body might attempt to adapt to this. I’ll let you know how it is going next week. In the meantime I off to have a mandarin and a glass of water :-)

 

Egyptian Army Claims Cure for HIV and Hepatitis C Michael Edmonds Jun 30

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Apparently the Egyptian army has developed a new cure for hepatitis C and HIV, described in the following video.

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The claims about this device contain many of the trappings of pseudoscience – a secretly developed device using “electromagnetic waves”, a conspiracy to suppress the invention, however, the obvious giveaway in this story is the inclusion of a device “invented” by the Egyptian military in 2010 to detect carriers of hepatitis C in a crowd. This detector, looks suspiciously like a device that previously has been sold as a bomb and drug detection device, despite the fact that it is little more than a modern dowsing rod (made up of a hinged aerial that waves from side to side).

Why the Egyptian military would be involved in such devices, I don’t know, but the potential harm is immense. Passing blood from the body, through a device and back again has associated hazards, and using the equivalent of a magic wand to determine who has hepatitis C and who does not, is horrifying. A misdiagnosis either way could have severe consequences for the patient, and society.

I hope someone in the Egyptian military and/or government comes to their senses quickly, to limit the harm that these devices could do.

 

Sir Peter Gluckman on New Zealand’s Childhood Obesity Epidemic Michael Edmonds Jun 09

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Yesterday on TV One’s Sunday programme there was an interview with Sir Peter Gluckman on New Zealand’s childhood obesity problems and his recent appointment to the Commission to End Childhood Obesity by the World Health Organisation. I thought it was an excellent interview (though personally I would avoid terms such as co-variates and multi-sectorial) highlighting the value of science in informing us about the issues involved.

The interview can be found here

“Legal Highs”, Testing, & Political Point Scoring Michael Edmonds Apr 29

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The removal of “legal highs” from shelves in two weeks, and the debate over using animals to test them, has science taking a backseat to politics as political parties line up to score points with the public.

“Legal highs” are being withdrawn from the market because they have never been tested in terms of their toxicity (which begs the question why were they ever made legal?). Politicians from the major parties are now saying they do not support testing of these drugs on animals (with accompanying video footage of them petting a cute furry animal) which leads to a catch 22 situation. How can you effectively test these substances without animal testing?

Several politicians have trotted out the “fact” that drugs can be tested using computer modelling and in test tube tests, however, this does not provide the full story. Even if such tests are carried out, animal testing will still be necessary to see how these drugs affect a living animal. It makes sense that you would need to test psychoactive substances which have the potential to be addictive on something with a nervous system (e.g. a living animal) at some stage during the testing.

Of course, there is an alternative to using animals – if these substances are made illegal they will go underground with people buying and using them most likely with little knowledge of what they are using, how pure it is, and what is a safe dosage. Couldn’t another possibility be to do medically monitored testing on volunteers to see what the effects are? If they are likely to use these substances anyway, why not use them in a controlled way?

One of the reasons legal highs have become popular is because cannabis is illegal. These to me seems rather absurd – people are using untested synthetic substances because they aren’t allowed to legally use a natural substance for which the effects are reasonably well researched. Perhaps if human testing were allowed, then cannabis could be tested along side these “legal highs”.

Personally, I would prefer it if these substances didn’t exist. I think any psychoactive drug must carry dangers with it – you are after all altering the chemistry of the brain when you use them! Unfortunately they do exist and whether legal or illegal people will continue to use them. No politician is brave enough to ban them outright. Instead they have chosen to use this catch 22 around requiring testing but not allowing testing on animals in order to offend the least number of voters.

The removal of these substances in such a short time frame has some mental health organisations concerned about the number of people they may have to deal with as they go through withdrawal from the legal highs. One has to wonder whether public health is also taking a back seat to politics.

Anyone would suspect it is an election year.

 

 

 

Energy Drinks in Schools – Let the Propaganda begin Michael Edmonds Jan 23

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This morning on Breakfast TV they talked about a recent proposal to ban energy drinks in schools. Having taught for a short period in high schools this seems like a good idea to me – teaching high school students can be hard enough without having some suffering the effects of drinks which are both high in caffeine and sugar.

Katherine Rich, spokesperson for the New Zealand Food and Grocery Council, an industry lobby group, was interviewed and during the interview stated several times that there was less coffee in energy drinks than in tea or coffee. This sounded wrong to me, as in the past I have had my students analyse the caffeine content of various drinks. So I wandered over the the supermarket this morning, checked a few cans of energy then consulted the literature. From this I constructed the following table:

Drink Average serving (mL) Amount of caffeine/serving
Brewed coffee (strong)

250

140 mg

Instant coffee

250

98 mg

Brewed Tea

250

58 mg

V double hit

500

155   mg

V blue

250

80 mg

V maximum

250

500

80 mg*

160 mg*

Lift + (green)

250

79 mg

Monster energy

550

176   mg

Red Bull

250

335

473

80 mg

107 mg

150   mg

Mother energy

500

160   mg

*contains guarana 300 mg

As you can see that if we were talking about the same serving size then Ms Rich is correct with regards to a strong or medium strength cup of coffee, though not with regards to tea based on the figures I obtained.

However, she has overlooked the fact that many energy drinks are sold in 500 (and one in 550 mL) cans. These deliver a dose higher than  your average cup of coffee, and much higher than tea.

Another oversight is that drinks such as V maximum also contain guarana and it is not clear to me from the labeling whether the stated amount of caffeine takes into account the caffeine which would be present in the 300 mg of guarana they add. If not the caffeine content should be higher than stated!

Of course comparing the amount of caffeine in energy drinks to that in coffee and tea is a bit of a red herring as I don’t think many schools would encourage students to drink tea or coffee. But then maybe this is simply an attempt to “normalise” the idea of caffeine consumption by children by linking it to commonly consumed drinks by adults.

Either way, it would be nice if people didn’t put a spin on the actual facts in such debates.

 

 

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