Showing posts with label malaria. Show all posts
Showing posts with label malaria. Show all posts

Saturday, February 11, 2012

Weekend Post: Good and bad news about malaria.

There’s good news and there’s bad news about malaria.

The bad news is that it’s possible we’ve ben grossly underestimating the number of deaths due to malaria over the last couple of decades. New research funded by the Bill and Melinda Gates Foundation and published in The Lancet and reported on the BBC suggests that the true death figures might be twice as high as we previously thought. For instance the World Health Organization estimated that in 2010 that 655,000 people died from malaria. The new research, which was based on a mixture of sophisticated statistical techniques and computer modeling estimated that malaria claimed 1.24 million lives around the world that year. The tragic news is that almost all of those deaths were here in Africa.

That’s the bad news.

The good news is that despite this tragic loss, the number of deaths is decreasing. While that figure is enormous, a mere six years beforehand the number was almost 2 million. The figure appears to have increased to that height in 2004 simply because there were more people living in affected areas. The subsequent drop was down to old-fashioned scientific progress.

I mean old-fashioned because it was based on theory, research and experimentation. In fact much of what was achieved was a wonderful mixture of leading edge science and some fairly old-fashioned techniques.

Not a single element of this progress was achieved using superstition, “alternative” medicine or pseudoscientific claptrap. No religion has ever saved this number of lives.

My favourite is the old-fashioned mosquito net. Nets have been used to prevent people being bitten by mosquitos for centuries. There are even stories that Cleopatra slept under one, two thousand years ago. The barrier idea is as old as the hills, just like the condom. The new element is that these nets can now be treated with a long-lasting insecticide. These insecticide treated nets, or ITNs, cost just a few US dollars and are considered by experts to be the single most effective way of preventing people getting malaria. Research has shown that they can reduce the number of episodes of malaria by up to half.

The nets don’t last forever of course and must be replaced once the insecticide has worn off but for only a few dollars a net that’s not such a huge problem, particularly when international health organisations and charities are paying for them. Better still if many people in a community use the nets the effect is to reduce the overall number of mosquitos in that area so even the neighbours who don’t have the ITNs get some benefit.

One of the interesting debates about ITNs is actually who should pay for them. Although Bill and Melinda Gates, the World Health Organisation and charities around the world are prepared to cough up the cash many experts feel that people will use the nets more if they contribute towards their cost themselves. The notion is that people feel a greater sense of emotional investment in something they’ve spent money on. A freebie is something you’ll care less about perhaps?

Almost as good, and perhaps one day even better, is the prospect of a vaccine against malaria. A couple of months ago a research scientist from GlaxoSmithKline, a drug company and therefore in many people’s minds utterly evil, announced some fantastic preliminary results. Following an 18-month clinical trial involving 15,000 African children an experimental vaccine appears to reduce the risk of contracting malaria by half.

I’m not going to defend the pharmaceutical industry against all the charges laid against it but every so often something like this comes along that is just simply good. A vaccine for malaria would be worth whatever it might cost to produce. The value in saved lives would be beyond a mere price.

Of course the real fantasy is what might happen if we can combine the treated nets AND the vaccine. Is it possible that malaria might go the way of smallpox? Until smallpox was eradicated many people thought it was an unachievable dream but science did that for us. Nobody will ever suffer from smallpox again. Maybe in our lifetimes the same can be said for malaria?

Sources

The BBC story can be seen here. A summary of the Lancet story is here.

For an overview of mosquito nets see the Wikipedia page here and for malaria see here. For the Reuters story on the GlaxoSmithKline vaccine see the story here.

Saturday, October 29, 2011

Weekend Post - A malaria vaccine?

Is it possible that we might one day live in a world without malaria? Nobody knows but we’re now a step closer.

Last week it was announced that following an 18-month clinical trial involving 15,000 African children an experimental vaccine appears to reduce the risk of contracting malaria by half. That’s not a cure but it’s an excellent start.

The potential benefit is enormous. Every year perhaps a million people around the world die from malaria, most of them African children. Anything we can do to reduce that death toll must be worth the effort. Even if we only halve the number of victims that’s half a million survivors.

This vaccine works by stopping the spread and multiplication of the malaria parasite after the victim has been bitten, by stimulating the body’s immune response and preventing it from getting a foothold in the liver.

The vaccine was based on a quarter of a century’s research by a GlaxoSmithKline team led by a research scientist called Joe Cohen. This is the stuff that Nobel Prizes are made of. A career’s research devoted to something that is so overwhelmingly good, that has such potential benefit for humanity and that can possibly save millions of lives.

I can’t help but wonder how certain people are going to react when they learn that this research was undertaken by a drug company. Not a high-brow academic in a university but an employee of GlaxoSmithKline, a company that some people will have you believe is the corporate Anti-Christ. I’m no defender of the pharmaceutical industry, they’ve certainly got a stained record but that doesn’t mean everything they do is wrong. This is a great example of how an absolute and uncomplicated good thing can come from an industry we’re free to criticise and condemn. Every so often though we have to give them some serious gratitude.

It’s happened before of course. One of the least known but most important statements ever made in human history was when the World Health Organisation declared in 1980 that “the world and its peoples have won freedom from smallpox”. A massive, worldwide campaign of vaccination and infection control over several decades eventually removed smallpox from the face of the planet. This disease killed hundreds of millions of people and it’s eradication is perhaps the greatest, practical contributions to humanity that science has ever offered. If you ever encounter one of those deluded scaremongers who say that vaccination is dangerous you need only say the word “Smallpox” and you’ve won.

One of the most disappointing things I’ve seen over the last few decades is the anti-vaccination movement. I have no hesitation in calling them either deluded or liars and some of them are both. Children have DIED because of the drops in vaccination rates around the world. Not just in the Western World where measles reappeared but here in Botswana where certain groups took what is politely referred to as a “faith position” against vaccinations. It’s not just their children we should feel sorry for it’s the rest of the community as well. One of the key objectives in fighting communicable disease is “herd” or “community immunity”. A disease like measles can’t spread as easily if most of the population are immune to it. “Chains of infection” can’t form if there are only very few people with no immunity. The more people there are who haven’t developed, or been given, immunity by vaccination the more likely the few who haven’t are to get the disease.

Malaria is different though, it’s not passed from human to human and eradicating malaria will require a different approach. However, a vaccination to give people immunity would be such an amazing step forward. The vaccine isn’t going to be with us very soon either. Scientists have earned the hard way that these things can’t be rushed. However the researchers hope that it’ll hopefully be available by 2015. Then we can really celebrate.

Sources

For a summary of the research see the Reuters story here. There's a comprehensive description of malaria from the Center for Disease Control here.

For some background on smallpox and why it's eradication is a reason for celebration see the Wikipedia page and the various links it offers. Anti-vaccination campaigners should be forced to look at the pictures of smallpox victims and imagine they show their children. For a scathing description of the loathsome anti-vaccination movement see the Skeptics Dictionary article here.