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Bird flu in humans confirmed
BEIJING CONFIRMED its first human cases of avian flu last week, shortly after the Chinese government announced plans for possibly the biggest vaccination campaign in global history covering the country’s entire poultry stock of 14 billion.
The measures, a sign of the authorities’ growing desperation, came as China reported its 11th outbreak of bird flu in little more than a month and acknowledged that the virus had claimed its first confirmed human victim, a 24-year-old woman in Anhui province, a poultry worker.
China also confirmed that a boy, aged nine, from Hunan province, who became sick last month but recovered, had the H5N1 virus. His 12-year-old sister fell ill and died though authorities cannot confirm she was a victim of bird flu because she was cremated before samples were taken. The government said earlier that the siblings were victims of pneumonia, though they became ill after eating sick chickens.
Adding to fears that the virus could mutate and lead to a global pandemic, Vietnamese scientists reported two new strains of the virus, which has killed at least 64 people, as well as ravaged poultry and forced a cull of tens of millions of birds across the region.
Since the outbreak in 2003 most of the reported casualties have been in south-east Asia. But in the past month China has become the new front line in the battle to control the disease.
The H5N1 pathogen kills birds in less than an hour. Transmission to humans is still rare but about 50 per cent of the people who have contracted the disease, mostly by handling poultry, have died. Health officials fear that as the pathogen spreads among birds the chances of it mutating into a form that can be passed between humans are increasing.
Meanwhile, scientists in Vietnam believe the H5N1 bird flu strain has mutated, allowing it to breed more effectively in mammals, though not necessarily in humans, online newspaper VnExpress said.
Scientists at the Pasteur Institute found significant variations in 24 samples from humans and poultry. The findings corroborate the belief that H5N1 would not have to mix with a human flu strain to become a form causing a human pandemic.
Ageing breakthrough claimed
A genetic experiment to unlock the secrets of the ageing process has created organisms that live six times their usual lifespan, raising hopes that it might be possible to slow ageing in humans.
The geneticists behind the study say the increase in lifespan is so striking, they may have tapped into one of the most fundamental mechanisms that controls the rate at which living creatures age.
The tests were carried out in single-celled organisms, forcing them into what the researchers refer to as an “extreme survival mode”. Instead of growing quickly and showing signs of ageing, the organisms became resilient and were better able to repair the genetic defects that build up with age, often leading to cancer in later life.
A large body of research has already shown that severely restricting diet can boost the lifespan of flies, worms and mice by around 40 per cent. Scientists believe that drastically cutting calories triggers a switch in an organism’s behaviour, from growing and being able to reproduce, to a state of stasis in which growth and ageing are put on hold at the expense of reproductive capability, until more food is available. Scientists are now trying to mimic the effect by tinkering with genes in the hope of developing anti-ageing treatments that work without having to cut food intake.
“We’re not too far from being able to exploit this understanding to at least start thinking about drugs that can put humans in an anti-ageing mode. That doesn’t mean we’ll necessarily live six times longer, but it means we could slow down the DNA damage we accumulate as we age, and that could protect us from cancer,” said Dr Longo.
Poor countries at great risk
The world’s poorest countries face a dramatic rise in deaths from disease and malnutrition as a direct result of climate change driven by wealthier, more polluting countries, scientists said last week.
The researchers reached the conclusion after constructing a map showing how climate change will affect different regions of the world by making infectious diseases more rampant and damaging local agriculture. The picture that emerges shows the least wealthy countries with the lowest greenhouse gas emissions as the most vulnerable.
They can expect a doubling of deaths from malaria, diarrhoeal diseases and malnutrition by 2030 as a result of climate change. In a previous study, the World Health Organization said climate change caused by industrial emissions already accounts for at least 5 million cases of illness and more than 150,000 deaths each year.
The scientists, whose research was published in Nature, created the map by collating published studies linking disease and agriculture to temperature and weather variations. One the studies showed that in certain South American countries, a 1C rise in temperature caused an 8 per cent increase in diarrhoeal diseases.
Blood vessels from skin
The first clinical trial to implant blood vessels grown entirely from a patient’s own cells was declared a success recently by a team of American scientists.
Two patients have so far received transplant blood vessels that were grown in a dish from a clump of their own skin cells. In both cases, the patients were said to be progressing well after their operations and the blood vessels were performing “perfectly”.
The veins were created in a laboratory by scientists at Cytograft Tissue Engineering, a biotechnology company based in California, before being transplanted into patients undergoing kidney dialysis to test whether they could withstand high blood pressures. The team is now embarking on an unprecedented trial at Papworth hospital in Cambridge, which will see lab-grown blood vessels used in heart bypass operations for the first time.
“This is a world first, so we are taking our time, but the results so far are extremely encouraging,” said Dr Todd McAllister, who announced results of the on-going trial in Chicago. — Dawn/The Guardian News Service
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