nature

Behind an unmarked door at the side of an anonymous second world war Nissen hut in the middle of Oxfordshire, a group of scientists are attending to the needs of hundreds of thousands of mosquitoes. They provide horse blood for the females to feed on, moist beds for them to lay their eggs, and add genes that transform the mosquitoes into what could be the most decisive tool yet invented to combat mosquito-borne disease.

The mosquitoes developed and raised here at the laboratories of Oxitec, a British biotech company based near Didcot, have already infiltrated wild populations in Brazil, Malaysia and the Cayman Islands, and will soon be unleashed in Panama and India. The company hopes that it will reduce populations of disease-carrying mosquitoes by 80% but public opposition to anything “genetically modified” remains a significant obstacle to the possibility of saving thousands of lives.

Mosquito-borne diseases are one of the major barriers preventing economic progress in the developing world. According to the World Health Organisation, 200 million people were victims of malaria in 2010 and 655,000, mostly children, died from it. Dengue fever is believed to affect 50-100 million people per year and results in around 20,000 deaths.

“From a scientific point of view and an environmental sustainability point of view, we think we have a really good solution to the problem,” says Hadyn Parry, the CEO of Oxitec.

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Unlike GM crops, Oxitec’s mosquitoes are not designed to spread their genes down the line or to other species. “We are not putting an advantage into these mosquitoes; we are putting in a disadvantage, sterility, which is the biggest disadvantage you can have,” says Parry. “You are not spreading your gene down generations because each one is sterile – it dies out. They do not out cross and mate with other species. So you are not spreading your gene laterally or downward.”

Critics of Oxitec say that the company is rushing to commercialise its products to provide a return on investment, massaging research while leaving key questions unanswered. Dr Helen Wallace, the director of GeneWatch, says she has several problems with Oxitec’s findings from its trials. One major issue, she says, is the occurrence of the tetracycline – the antibiotic that the young mosquitoes need to survive – in livestock and meat. Theoretically, if a female mosquito, daughter to a modified one, bit meat or an animal that contained tetracycline, she could survive. Oxitec says that the chance of this happening is very slim and in its most recent trial in the Caymans, it did not find a single mosquito that had survived.

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A study into whether physical activity alleviates the symptoms of depression has found there is no benefit.

Research published in the British Medical Journal suggests that adding a physical activity intervention to usual care did not reduce symptoms of depression more than usual care alone.

This contrasts with current clinical guidance which recommends exercise to help those suffering from the mental illness, which affects one in six adults in Britain at any one time.

To carry out the study researchers recruited 361 patients aged 18 to 69 years who had recently been diagnosed with depression.

Trial participants were then split into two groups to receive either the physical activity intervention in addition to usual care, or usual care on its own and were followed up for 12 months to assess any change in their symptoms.

But the study found that adding exercise failed to alleviate symptoms of depression more than usual care alone, only increasing levels of physical activity.

[carry on reading via the guardian]

One of the most fascinating and affecting pieces of journalism I have ever read appeared in an edition of Rolling Stone magazine in early 2007. An investigation into pig farming, and more specifically the environmental impact of America’s top pork producer, Smithfield Foods, it spoke of how “500,000 pigs at a single Smithfield subsidiary in Utah generate more faecal matter each year than the 1.5 million inhabitants of Manhattan” and estimated that this one company alone produced more than 26m tonnes of waste annually. “A lot of pig shit is one thing,” the article’s author, Jeff Tietz, remarked. “A lot of highly toxic pig shit is another.”

It was Smithfield Foods I thought of this week, when I read of a report published in Environmental Research Letters, which advised that we reduce meat consumption by 50% over the next 40 years if we are to save ourselves from environmental catastrophe.

The author of the report, Eric Davidson of the Woods Hole Research Centre in Massachusetts, advised that with great urgency we must cut back on both portion size and the quantity of meat we eat in an effort to reduce the amount of fertiliser we currently use – particularly in the west, but also in developing nations, where increasing prosperity has also brought a rise in meat consumption.

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All of this has repercussions – not only for our waistbands, or even the fact that producing clothes to fit those expanding waistbands requires the production of more fabric; and not even just for our own health, the strain on our hearts and lungs, the drain on our health services, the vast sums we spew on diet products and gym membership, the cost of building bigger aeroplane seats, cars and coffins to accommodate our growing bodies. No, our slavering greed, our lust for enormous portions, affects how much meat our farming industry is expected to produce – and not only produce, but produce quickly and cheaply; demands that increase the need for fertilisers, insecticides, antibiotics.

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But if we have learned anything from the current economic crisis, it should surely be that we cannot expect to have jam today and jam tomorrow. In environmental terms, we have bought on credit, we have maxed out our cards and gone way, way over our overdrafts.

And maybe what will save us is a great scientific bailout: a grand solution of artificially created meat, or a new generation of fertilisers, or robot bees, or whatever. Or maybe, just maybe, it’s time for us to exercise a little self-restraint.

*Share your thoughts*

[click link above to carry on reading | words by Laura Barton]

The global fight against malaria is being threatened by growing resistance to powerful new drugs which have become one of the most important weapons in the battle.

Experts say that the medical effects of artemisinin-based compounds, being used to treat people around the Burma/Thailand border, are weakening. Where there were once apparently miraculous recoveries of children treated with artemisinin-combination therapy (ACT) now the treatments take longer to be effective.

Doctors envisage a time, when, if nothing is done, the drugs will cease to work at all.

Malaria parasite resistance to the drugs has been identified in western Cambodia but it was hoped that tough controls would contain it. Now, however, scientists say there are real problems in Burma – and they warn that resistance there must be tackled if it is not to spread worldwide.

They warn that history is repeating itself: resistance is appearing and artemisinin is losing its potency just as happened with older drugs, like chloroquine, and it is beginning in exactly the same places on the map.

The discovery of resistance to drugs – which have, with insecticide-impregnated bednets, altered the course of the malaria epidemic – “threatens worldwide initiatives to control and eliminate malaria”, reports a paper in the Lancet.

The paper is one of two by teams of scientists who have studied the growth of resistance on the Thai/Burmese border. “Resistance to the previous mainstays of antimalarial treatment, namely, chloroquine and sulfadoxine-pyrimethamine, also arose in western Cambodia and spread across South-east Asia into Africa, resulting in the deaths of millions of children.”

[click the link above to carry on reading | words by Sarah Boseley]

A simple blood test capable of identifying lung cancer at an early stage is to be trialled by the NHS on thousands of smokers.

It his hoped the new test, developed in Britain and already piloted in the US, will drastically cut death rates, reduce medical bills and lead to an overhaul in the way cancer is diagnosed and treated.

Sir Harry Burns, Scotland’s chief medical officer, said the trial would involve 10,000 patients, mainly smokers, identified as having a higher risk of developing the disease. If successful, the £200-per-person procedure could be rolled out across the rest of the country.

“The earlier a cancer is diagnosed the greater the chance it can be treated successfully, and currently 85% of patients with lung cancer remain undiagnosed until the disease has reached an advanced stage,” Burns said. He said the detection programme aimed to increase early diagnosis by 25%.

Known as EarlyCDT-Lung, the test tracks increases in blood antibody levels that could signal the onset of cancer. Patients with raised levels will be referred for a CT scan – the x-ray-style imaging currently used to detect the disease.

[click the like above to carry on reading | words by Barry Neild]

Urban air pollution is set to become the biggest environmental cause of premature death in the coming decades, overtaking even such mass killers as poor sanitation and a lack of clean drinking water, according to a new report.

Both developed and developing countries will be hit, and by 2050, there could be 3.6 million premature deaths a year from exposure to particulate matter, most of them in China and India. But rich countries will suffer worse effects from exposure to ground-level ozone, because of their ageing populations – older people are more susceptible.

The warning comes in a new report from the Organisation for Economic Cooperation and Development (OECD), which is a study of the global environmental outlook until 2050. The report found four key areas that are of most concern – climate change, loss of biodiversity, water and the health impacts of pollution.

If current policies are allowed to carry on, the world will far exceed the levels of greenhouse gas emissions that scientists say are safe, the report found. “I call it the surrender scenario – where we would be if governments do nothing more than what they have pledged already?” said Simon Upton, environment director at the OECD. “But it could be even worse than that, we’ve found.”

[click the link above to carry on reading | words by Fiona Harvey]