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Archived News Week ending April 3rd, 2008
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Veterinary staff in eastern India are capturing chickens in night-time raids on the backyards of homes to surprise villagers unwilling to part with their poultry as an outbreak of bird flu spread.
Bird flu has spread to 13 of West Bengal's 19 districts, with samples of dead chickens testing positive in two new districts, officials said on Monday. In neighboring Bangladesh, the disease has spread to 29 of the its 64 districts.
Experts fear the H5N1 strain found in both countries could mutate into a form easily transmitted from person to person, leading to a pandemic, but there have been no reported human infections in India yet.
"It is very difficult to contain the virus among backyard poultry as villagers hide their chickens and even smuggle it to homes of distant relatives," said Anisur Rahaman, the state's animal resources minister.
Officials said they were worried about the disease spreading to the crowded state capital, Kolkata, after bird flu hit the South 24 Parganas district on Sunday, only 20 km (12.5 miles) away from the city.
Surveillance was in place to stop infected poultry from being smuggled into one of India's biggest cities, they said.
Authorities also used loudspeakers and distributed leaflets in villages, urging people to hand over poultry to culling teams.
Villagers say government compensation of a dollar a bird was not enough...
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A new study reveals a dark side to research and ecotourism, both of which ironically are aimed to help the apes and which may still do more good than harm.
Scientists investigated chimpanzees hit by five outbreaks of respiratory disease between 1999 and 2006 in Côte d'Ivoire in West Africa. Nearly all the endangered chimps became sick and many died.
All available tissue samples gathered from chimp victims tested positive for one of two germs — human respiratory syncytial virus (HRSV) or human metapneumovirus (HMPV). These viruses often cause respiratory disease in humans and, in developing countries, are a major source of infant mortality.
"The viruses we found are very common," said researcher Fabian Leendertz, a wildlife epidemiologist at the Robert Koch-Institute and Max Planck Institute for Evolutionary Anthropology in Germany. "Antibody prevalence in humans is almost up to 100 percent, meaning almost everybody has had contact with these viruses" and developed antibodies, naturally, designed to fight the germs.
These cases represent the first confirmed evidence of viruses transmitted directly from humans to wild great apes.
"Virtually all diseases that can harm us can harm the great apes since we share so many genetic and physiologic properties," Leendertz told LiveScience.
There is a long history of diseases spreading from great apes to humans, and perhaps from humans to great apes:
* Ebola is a widespread threat to gorillas and chimps in Central Africa, and may have spread to humans from people who ate infected animals. Ebola and SARS may both have originally come from bats.
* HIV, the virus that causes AIDS, originated from chimps and other primates.
* Gorillas may have given humans pubic lice, or "the crabs."
* There have been suspicions that chimps at Gombe Stream National Park in Tanzania contracted polio from humans, Leendertz said.
* There have also been concerns that gorillas contracted yaws, a disease related to syphilis that is not sexually transmitted, from humans, Leendertz added.
* Gorillas and chimpanzees in West Africa have been killed by outbreaks of anthrax. This may have originated from cattle herded by humans, although Leendertz noted these may have been natural events that just exist there in the forests.
Although research and ecotourism efforts have brought people into greater contact with endangered great apes in the wild, potentially threatening the primates, "research and tourism has a strong positive effect on great apes' survival since it reduces poaching activities in these...
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Scientists have made the lethal virus Ebola harmless in the lab, potentially aiding research into a vaccine or cure.
Taking a single gene from the virus stops it replicating, US scientists wrote in the Proceedings of the National Academy of Sciences journal. Ebola, currently handled in highly secure labs, kills up to 80% of those it infects. However, one expert said the new method may not yet be a fail-safe way of dealing with the virus.
The need for a "biosecurity level 4" (BSL4) laboratory for any work involving Ebola means that very few research institutions are capable of doing this.
Researchers wear biosafety suits with their own air supply, and the air pressure in the room is less than the pressure outside, so any leak would mean air flowing inwards rather than outwards.
This makes anything more than small-scale study of the virus very difficult to arrange.
If Ebola could be kept in a viable form, yet with the risk of infection removed, then conventional labs might be able to study it.
The researchers, from the University of Wisconsin at Madison, say that they have found a "great system" to do this.
They said that a single one of Ebola's eight genes, called VP30, is the key, as without it, the virus cannot replicate within host cells by itself.
Initial symptoms include high fever, severe headache, muscle, joint, or abdominal pain, severe weakness and exhaustion, sore throat, and nausea
As the infection progresses more serious symptoms include diarrhoea, vomiting blood, organ damage, and internal bleeding
However, the scientists still want the virus to replicate in order to study it, so they developed monkey kidney cells which contained the protein needed.
Because the cell was providing the protein, and not the virus itself, it could only replicate within those cells, and even if transferred into a human, would be harmless....
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Officials in the Indian state of West Bengal say that the bird flu epidemic has spread to two more of the state's 19 districts, taking the total to nine.
They say that the spread of the H5N1 virus means that even more chicken and duck will have to be killed than was originally estimated.
On Monday officials said that around 2m birds would need to be culled - a figure that will now rise.
Health experts have warned that the outbreak could get out of control.
The H5N1 strain of bird flu is regarded as highly pathogenic and can also cause disease and death in humans.
However, most human victims have contracted the disease through close contact with affected birds.
There is little evidence that the virus can be transmitted easily between humans.
West Bengal's Minister for animal resources and development, Anisur Rehman, told the BBC there are currently 650 culling teams in the state who have killed about 430,000 birds with another 200,000 expected to be destroyed on Wednesday.
Birds being taken for culling in West Bengal
Villagers are reported to be reluctant to hand over birds
They have now been ordered to extend their chicken and duck killing operation from seven to nine districts.
He said that one of the districts most recently affected, Hoogly, is close to Calcutta and contains the state's largest chicken hatchery - which has not yet been affected....
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an Francisco General Hospital researchers have been chasing the rogue strain of drug-resistant staph called USA300 since they first isolated it from a patient specimen seven years ago.
With every turn, the aggressive and persistent bug keeps getting worse.
Now, a new variant of that strain, resistant to six major kinds of antibiotics, is spreading among gay men in San Francisco, Boston, New York and Los Angeles.
City doctors first spotted the original USA300 during tests for patients treated at a walk-in clinic for skin infections in 2001. Since then, they have watched it morph from laboratory curiosity into the dominant form of staph infection in much of the United States.
"It stormed into town and just took over, displacing everything else," said Dr. Chip Chambers, infectious disease chief for the renowned hospital.
At first, USA300 hit the down-and-out: injection-drug users, jail inmates, homeless men and women. Today it is also infecting suburban moms, executives, doctors, athletes and children. It has turned up in tattoo parlors and newborn nurseries. People with HIV infection seem especially prone to it, but it also strikes patients, gay and straight, who have no previous health problems.
Staph infections are usually treatable but can be lethal. USA300 is as dangerous as they come - it can attack organs throughout the body, forcing doctors to amputate fingers, toes and limbs. Its most disturbing trait, however, is just how easily it gets around.
"USA300 has a tremendous ability to spread," said Francoise Perdreau-Remington, director of the molecular epidemiology lab at San Francisco General, where the strain was first identified. "It has been described in at least 44 states and is now spreading in European countries."
USA300 is one of a dozen distinct varieties of MRSA, or methicillin-resistant Staphylococcus aureus, now circulating. The first MRSA strain, resistant to the penicillin substitute methicillin, was discovered in 1961. It continues to evolve. More than 200 families of the strain have come and gone since. USA300 is shaping up as the worst of the lot.
The various MRSA families have been gaining strength as a public health menace for years.
MRSA infections used to be confined to hospitalized patients. But in the late 1990s, people began contracting them in community settings - in gyms, jails, schools and even at home. The federal Centers for Disease Control and Prevention calculated last fall that drug-resistant staph was killing 19,000 Americans a year - more than are dying ...
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At a busy microbiology lab in San Francisco, bad bugs are brewing inside vials of human blood, or sprouting inside petri dishes, all in preparation for a battery of tests.
These tests will tell doctors at UCSF Medical Center which kinds of bacteria are infecting their patients, and which antibiotics have the best chance to knock those infections down.
With disturbing regularity, the list of available options is short, and it is getting shorter.
Dr. Jeff Brooks has been director of the UCSF lab for 29 years, and has watched with a mixture of fascination and dread how bacteria once tamed by antibiotics evolve rapidly into forms that practically no drug can treat.
"These organisms are very small," he said, "but they are still smarter than we are."
Among the most alarming of these is MRSA, or methicillin-resistant Staphylococcus aureus, a bug that used to be confined to vulnerable hospital patients, but now is infecting otherwise healthy people in schools, gymnasiums and the home.
As MRSA continues its natural evolution, even more drug-resistant strains are emerging. The most aggressive of these is one called USA300.
Last week, doctors at San Francisco General Hospital reported that a variant of that strain, resistant to six important antibiotics normally used to treat staph, may be transmitted by sexual contact and is spreading among gay men in San Francisco, Boston, New York and Los Angeles.
Yet the problem goes far beyond one bug and a handful of drugs. Entire classes of mainstay antibiotics are being threatened with obsolescence, and bugs far more dangerous than staph are evolving in ominous ways.
"We are on the verge of losing control of the situation, particularly in the hospitals," said Dr. Chip Chambers, chief of infectious disease at San Francisco General Hospital.
The reasons for increasing drug resistance are well known:
- Overuse of antibiotics, which speeds the natural evolution of bacteria, promoting new mutant strains resistant to those drugs. ...
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Three mute swans in Dorset have been found dead with the virulent H5N1 strain of bird flu.
Other birds are being tested at Abbotsbury Swannery, near Weymouth, but so far culling has been ruled out. Acting Chief Veterinary Officer Fred Landeg said: "Our message to all bird keepers, particularly those in the area, is that they must be vigilant." Prime Minister Gordon Brown said the government would do "everything we can" to stop the spread of infection.
He said: "We have had to deal with this issue before and the important thing is that people know we have placed protection zones around the affected area."
The swans' carcasses were found following routine surveillance, a statement from Defra said.
Defra said government vets had been testing them for avian flu for the last two days.
Culling of wild birds has been ruled out because experts fear this may disperse birds further.
It has set up two restricted areas - a wild bird control area and a larger wild bird monitoring area.
The control area extends approximately 15 miles (25km) to the south east of Abbotsbury, and includes the town of Weymouth, Chesil Beach and the Portland Bill headland.
Bird owners must isolate their flocks from wild birds within the zone.
Defra said the size and shape of the zone was decided based on expert ornithological advice.
John Houston from Abbotsbury Swannery, which holds 600 swans, said staff were working closely with Defra officials.
He said: "We are very concerned, but we have been encouraged by Defra's comments about the situation of outbreaks in wild ducks.
"In those, experience has been a very low mortality of the ducks, perhaps only 1%, and almost immediately or very quickly there has been a build-up of immunity to the virus within the ducks.
"We are hoping that that scenario within the ducks will be repeated by the swans here at Abbotsbury."
He said staff entering the site were wearing protective suits, and removing them and disinfecting themselves on leaving.
"We are also working with the Health Protection Agency to ensure that staff and public are fully protected."
It does seem to be the case that we are going to have to live with this particularly virulent disease
Conservative MP Oliver Letwin, whose West Dorset constituency includes Abbotsbury, said he was glad to see the outbreak being "treated with the seriousness which it deserves".
"I very much hope that we will get through this with the swannery intact because it is a remarkable national institution of real beauty and real ecological significance," he said.
The discovery in Dorset is the latest in a series of bird flu cases in the UK.
In November 2007, around 5,000 birds were slaughtered after the H5 strain of avian flu was confirmed in turkeys at Redgrave Park Farm, Suffolk.
Previously, a strain was found in chickens at a Norfolk farm in April 2006 and the month before that the deadly H5N1 strain was found in a dead swan on the Fife coast.
Andre Farrar of the RSPB said no-one should be surprised that there had been a further case of H5N1 in the wild bird population....
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