The Schmallenberg virus causes serious birth defects and has spread from Germany to Britain
A new livestock disease – first detected six months ago in Germany – threatens farmers in northern Europe, including Britain. it causes a high level of miscarriage and birth defects in lambs and calves.
Veterinary scientists are scrambling to understand Schmallenberg virus, which is named after the site of an early outbreak. They believe the virus is spread by midges – like bluetongue fever, another serious disease of ruminants.
Schmallenberg has hit several hundred farms in Germany, the Netherlands, Belgium and north-east France. Infected midges, blown across from the continent, are probably responsible for the dozen or so outbreaks reported in Britain. all the UK farms affected are in south-east England and East Anglia.
“Everyone is wondering whether the cases detected so far are just the tip of the iceberg and this will turn out to be a serious threat to livestock farmers – or whether it will soon disappear again,” says Peter Mertens, head of the vector-borne diseases programme at the UK Institute for Animal Health.
Although the virus can cause symptoms in adult livestock, such as fever, diarrhoea and reduced milk yield, its main impact is on the growing foetus. Horrific malformations and miscarriages occur in an estimated third to a half of cases when the mother is infected. Experts, therefore, fear that many more cases will be reported during the spring lambing and calving seasons.
According to an initial assessment by public health authorities in the Netherlands and a follow-up analysis by the European Centre for Disease Prevention and Control, the risk to humans from Schmallenberg virus is very low. but the UK Animal Health and Veterinary Laboratories Agency points out that there are still some uncertainties, so farmers and vets are advised to “take sensible hygiene precautions when working with livestock.”
Schmallenberg is a member of a large viral family transmitted mainly by insects and affecting ruminant animals, called the orthobunyavirus group. few are known to cause serious human disease. when bluetongue emerged suddenly as a serious threat to European livestock in 2006/07, animal health researchers in the public and private sectors moved very fast to develop and use a vaccine against the viral strains responsible. “Bluetongue was an almost perfect scenario for stopping a disease through vaccination,” says Mertens. “It has been eradicated in the UK.”
Whether it will be technically possible to develop a Schmallenberg vaccine so fast – and whether the disease is serious enough to justify a crash programme to do so – remains to be seen.
…………………………………………….
Little Ice Age triggered by volcanic eruptions
For more than a millennium up to the late Middle Ages, temperate regions of the northern hemisphere enjoyed generally balmy weather. Then it got cooler and a period that climatologists today call the Little Ice Age set in.
There has been little scientific consensus about the onset of the Little Ice Age – either its timing or cause. Some experts believe an important factor was a slight reduction in the amount of solar energy reaching earth.
But an international study, led by the University of Colorado, Boulder, suggests that the cooling started quite rapidly, with a series of four huge volcanic eruptions between 1275 and 1300. these eruptions blasted vast amounts of sulphates and dust particles into the upper atmosphere, reflecting solar energy back into space for a few years. this led to an expansion of Arctic ice and a related change in Atlantic Ocean currents, which prolonged the cooling for several centuries.
“This is the first time anyone has clearly identified the specific onset of the cold times marking the start of the Little Ice Age,” says Gifford Miller, lead author of the study published in Geophysical Research Letters.
The researchers reached their conclusions by analysing ancient samples of dead plants collected from beneath the margins of what are today receding ice caps on Canada’s Baffin Island.
They found a cluster of “kill dates” between 1275 and 1300, showing that the plants were quickly engulfed by expanding ice. Confirmation came from ice cores of Iceland’s Langjökull ice cap, which suddenly thickened over the same period. Then computer modelling showed how this cold shock could persist for centuries, even without further volcanic cooling.
“If the climate system is hit again and again by cold conditions over a relatively short period – in this case from volcanic eruptions – there appears to be a cumulative cooling effect,” Miller says.
…………………………………………….
Camera sees coral reef in a new light
A coral reef looks very different to the creatures that live there than it does to human divers ooh-ing and aah-ing at the coloured marine life.
A shrimp poses for the polarised camera
Now researchers at the University of Bristol have developed a specialised camera that allows scientists to see the reef as some of its inhabitants do. The camera captures an aspect of light to which humans are essentially blind: its polarisation. Many marine animals are sensitive to polarised light, whose waves are vibrating more in some directions than others.
The Bristol team will take the camera to Australia’s Lizard Island to capture images of the Great Barrier Reef, which they hope will provide new insight into this underwater world. The camera converts its images into false colours that represent different polarisations of light.
“Many reef-dwelling animals, like octopus, crabs, shrimp and maybe even some fish, are sensitive to polarised light,” says Shelby Temple, project leader. “It’s hard for us to understand what that means because we really can’t see the polarisation of light without some kind of aid, like polarised glasses or specialised polarisation converting cameras like this one.”
Preliminary results suggest this dimension of the underwater world is more complex than previously thought. “There’s evidence that all types of communication and camouflage are going on, which we’ve essentially been blind to,” says Temple.
…………………………………………….
Official: massage has the feel good factor
Scientists now have a molecular explanation for the way massage relieves pain and reduces inflammation in muscles after strenuous exercise.
A study at McMaster University in Ontario and the Buck Institute for Research on Aging in California shows that massage stimulates muscle cells to produce numerous anti-inflammatory and pain-killing factors. it also promotes the growth of mitochondria, which produce the energy to power cells.
But surprisingly the research, published online by the journal Science Translational Medicine, demolished one oft-repeated idea: massage turns out not to help clear the lactic acid that may cause pain when it builds up in tired muscles.
The researchers analysed muscle biopsies taken from the legs of 11 young men who had exercised to exhaustion on a stationary bicycle. One leg was randomly chosen for a 10-minute massage. Biopsies were taken from both legs before the exercise, immediately after the massage treatment and two and a half hours later.
Simon Melov of Buck says the pain reduction associated with massage may involve the same mechanism as anti-inflammatory drugs. “There’s general agreement that massage feels good – now we have a scientific basis for the experience,” he says.
“The potential benefits of massage could be useful to a broad spectrum of individuals including the elderly, those suffering from musculoskeletal injuries and patients with chronic inflammatory disease,” adds Mark Tarnopolsky of McMaster.