Berikut merupakan kutipan ilmiah kedokteran yang sangat bermanfaat bagi Penulis sehingga digunakan sebagai referensi pribadi.
The country's Ministry of Health also said a woman suspected of having the disease had died earlier this month.
The dead woman was the mother of one of those confirmed as being infected. A second suspected case has also been reported.
It is thought that the cases can be traced back to the Center for Disease Control in Beijing, where one of the confirmed cases worked.
 |  Experts have reached the tentative conclusion that this outbreak can be traced back to infection by laboratory workers 
Chinese Ministry of Health statement
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Sars first emerged in the southern province of Guangdong late in 2002. Eight thousand people were infected in the outbreak, and 800 died.
China has announced it was on an emergency footing against the disease and said anyone found with a fever at the border would be quarantined.
Fever
In a statement released on Friday, the Ministry of Health said: "Experts have reached the tentative conclusion that this outbreak can be traced back to infection by laboratory workers."
It added that one of the confirmed cases, a 26-year-old medical student identified by her surname Song, conducted research at the laboratory for two weeks last month.
She later returned to her home in the Anhui province, eastern China, where she was hospitalised with a fever.
The woman was cared for by her mother who died earlier this week. Post-mortem tests have not yet established for certain whether she died from Sars.
The second confirmed case, a 20-year-old Beijing nurse Li Na, worked in the respiratory department of Jiangong hospital, where Song had been briefly care for before going home to Anhui.
A hospital official said all colleagues who had contact with her had been quarantined.
The second suspected Sars case also had ties to the Center for Disease Control.
The patient, a 31-year-old researcher, had worked at the centre's laboratory.
Authorities have tried to contain the outbreak by placing over 100 people who had been in contact with the Anhui cases under observation.
In Beijing, 188 people were deemed to have been in close contact with the 20-year-old nurse. Five have developed fever and other Sars symptoms, the health ministry said.
Reappearance
China also confirmed four cases of Sars in Guangdong earlier this year, all of whom recovered.
Scientists have always predicted that Sars would reappear - but they say the number of cases was unlikely to reach the scale of the 2002 to 2003 outbreak.
They said this was most likely to happen during the flu season.
The best way to contain the spread of Sars is to isolate people with the virus and those who have come into contact with them.
A failure to do this during the outbreak was blamed for the spread of cases across the world.
The virus is believed to have originated in China's southern Guangdong province in November 2002, and spread around the world by air travellers in February.
Sars is a serious respiratory virus, which killed nearly 800 people worldwide in the months following its emergence in November 2002.
The World Health Organization announced that the outbreak had been contained in the following July.
However, experts predict the virus will continue to pose a threat - and warn that health authorities need to be ever vigilant for its return.
When is Sars likely to pose the biggest threat?
Scientists predict that the virus which causes Sars is likely to re-emerge in cold weather, in a similar fashion to the viruses which cause flu.
However, they have stressed that the number of cases is unlikely to be on the scale of the 2002/03 outbreak.
What are the dangers of Sars spreading?
The best way to stop the spread of Sars is to isolate people with the virus and those thought to have been in contact with them.
In this case, officials have quarantined 25 people who have been in contact with the patient.
They have been ordered to stay at home to minimise any risk of the virus spreading.
However, officials have stressed they believe this is an isolated case.
How did Sars virus first come to the world's attention?
The first reports of an infection followed the death of a US businessman in a Hong Kong hospital in mid-March.
The man had visited China and Vietnam - hospital staff there and in Hong Kong subsequently fell ill.
However, the virus is believed to have originated in China's southern Guangdong province in November, and was spread around the world by air travellers in February.
What are the symptoms?
Experts believe that after infection with Sars, the incubation period can be up to 10 days.
Known symptoms are similar to those of flu, including high fever, headache, sore throat, and cough.
Patients who have recently returned from a country where Sars is prevalent - or who believe they have been exposed to an infected person - should consult a doctor if they develop these symptoms.
At present, the mortality rate is approximately 4% - four cases in 100 are fatal.
However, this may vary depending on the quality of medical care available.
Is there a treatment or vaccine?
There is no vaccine. There is also no specific antiviral treatment designed to treat Sars.
However, a cocktail of antivirals and antibiotics appears to be beneficial if treatment is started early.
In some cases of Sars pneumonia has developed, with patients finding it very hard to breathe - some have required artificial ventilation in hospital.
What causes the infection?
Scientists now believe they have confirmed the culprit.
The scientists, from the US Centers for Disease Control, believe it is Corona virus - a family of viruses well known as a cause of the common cold.
The WHO believes this is a new strain which has mutated to become more dangerous to humans.
Health officials have become particularly concerned about a jump in the number of young people infected.
Many of the deaths have been among the elderly, but fatalities have also included an otherwise healthy 37-year-old man in Hong Kong and two people in their mid-50s.
How can I catch it?
It is likely that infection takes place through droplets of body fluids - produced by sneezing or coughing.
An official report into a mass outbreak in a Hong Kong apartment block concluded that the virus had spread through a sewage pipe.
The WHO did not rule out the possibility that it may also be transmitted when people touch objects such as lift buttons.
Last year, Hong Kong has advised people to avoid crowded places and confined spaces.
Airlines insist that an infected person cannot spread the virus throughout an aircraft.
However, the WHO says that people sitting within two rows may be at risk.
What can I do to protect myself?
Some people in east Asia have taken to wearing face masks, but it is unclear exactly how much protection they offer against viral particles.
Professor John Oxford, a virology expert from Queen Mary's College in London, told BBC News Online: "There's not much you can do to avoid this, unless you go and live as a hermit.
What did governments and experts - and airlines - do to stop it?
The WHO global alert triggered responses from health experts in dozens of countries.
Doctors were asked to look out for cases, particularly arising in patients who have recently returned from abroad, and notify public health services so that the spread of the illness could be monitored.
Airlines were asked to look out for passengers who appeared unwell while checking in.
They were also been advised to disinfect aircraft in an attempt to stop its spread.
What advice does the UK government have for travellers?
The Department of Health says there are no current Sars-related travel restrictions .
But it says travellers should be aware of Sars symptoms and seek medical advice if the develop them within 10 days of returning from an affected area.
The latest advice is published on the Department of Health website.
Scientists say they have developed a new test for the virus that causes Sars which could lead to earlier detection of the disease.
The procedure, developed by the National Taiwan University, produces results in two to three days.
Other tests which look for antibodies produced by the body to fight the Corona Virus can take much longer.
The earlier a case of Sars is detected, the less chance there is that a patient will spread the disease to others.
The new test picks up substances called antigens which are produced by the virus.
These are the compounds which trigger the body's immune system to product antibodies to try to fend off the virus' attack.
Many of the other tests for Sars developed last winter only work once the antibodies have been produced.
The researchers in Taiwan say their procedure has proved to be accurate in a much shorter timeframe than those existing tests.
Researcher Chang Ming-fu said: "The testings have displayed a high degree of accuracy."
Safer collection
They have also developed a new method to collect specimens from patients' saliva by rinsing the mouth with water.
This means that healthworkers can reduce their chances of catching the Sars virus because they do not have to get close to the patient to carry out a throat swab to collect saliva for the tests.
The World Health Organisation says Sars has killed more than 770 people world-wide.
Many of those were healthworkers treating infected patients.
Outbreaks in Taiwan, Hong Kong and China affected thousands of people and caused damage to their economies from which they are only now recovering.
A spokesperson for the UK Health Protection Agency told BBC News Online: "It is inevitable that we will see an upsurge in the number of new tests for Sars and one of the biggest gaps in the diagnosis of Sars is the early detection of the disease, so tests such as this which specifically address this issue are welcomed.
"However, it is important that each new test is evaluated for its effectiveness and accuracy."
China's last two Sars patients have been discharged from a Beijing hospital after more than 100 days of treatment.
Lu Zhiyan, a 45-year-old medical worker, and 19-year-old student Sun Zheng left Ditan Hospital amid a sea of flowers and speeches hailing China's victory against Sars.
But health officials remain wary that the disease could re-emerge and are drawing up measures to fight any future epidemics.
Mainland China was hardest hit by the virus with 348 deaths out of a worldwide total of more than 800.
The discharge of the last two Sars patients marks the closing of a terrible chapter for the country and the official ceremony was determinedly upbeat.
A banner at the entrance of the hospital read, "Goodbye Sars, let's move on to tomorrow."
|  We must continue our anti-Sars work just as diligently as we have so far 
Niu Youcheng
Beijing's health department |
Sun Zheng, who had been hospitalised with Lu Zhiyan since April, told hospital staff: "Because of you, I am standing here today."
And the staff themselves were celebrating.
"I'm relieved," said Wang Guangmin, a doctor who was forced to stay at the hospital for three months at the height of the epidemic, unable to see his wife or seven-year-old son.
"In the beginning, when we didn't know what Sars was, it was very scary, and later on, it just became a lot of hard work," he told French news agency AFP.
'Fight not over'
Wang Guangmin is concerned Sars may return this winter, but added, "the resistance in the general population has improved, and we have early-warning systems in place".
Chinese health officials are also optimistic, while accepting they cannot be complacent.
Hospital staff say they are relieved the Sars fight is over
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"We are winning," said Niu Youcheng, an administrator at Beijing's Health Department.
"This fight against Sars has brought our society to a new level and made us more able," he said. "But we must continue our anti-Sars work just as diligently as we have so far."
This is echoed by the World Health Organisation's chief in China, Henk Bekedam.
"While one chapter has been closed, the fight against Sars is not over," he said. "We must remain vigilant, and we cannot know for certain whether Sars will return again."
A team of international experts is currently in China's southern Guangdong province trying to reach a firm conclusion on whether or not Sars originated in the animal population.
The Corona virus responsible for Sars has been found in the civet cat, a popular delicacy in Guangdong, which has already lifted restrictions on the sale of 54 kinds of wild animal.
Health officials fear the move may be premature. "There have been some very clear indications that the civet cat is linked," said Mr Bekedam. "We think it's a little early to lift the restrictions."
A team of international experts has arrived in southern China to study links between animals and the deadly pneumonia-like Sars virus, which killed more than 800 people worldwide earlier this year.
The experts, including World Health Organisation scientists, are visiting livestock farms, markets and restaurants in Guangdong Province, where the disease is believed to have started.
People in the province are known for their taste for eating exotic animals.
In Hong Kong, an epidemiologist has put forward a new theory to explain the rapid spread of the virus in the territory.
Writing in the Lancet science magazine, Stephen Ng from Columbia University School of Public Health in the US said rats living in pipes and light wells quickly spread Sars among the residents of the Amoy Gardens high-rise housing estate, after one of the rodents was infected by a human.
| I suggest the epidemic could have been started by a rat going into an apartment visited by the patient and being infected by contaminated material, such as used tissue paper, leftover food, or excreta
Epidemiologist Stephen Ng
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A total of 321 people living in 15 blocks in the territory fell sick with Sars from late march to mid-April.
Mr Ng's theory challenges a government inquiry in Hong Kong which found that the initial source of the Sars outbreak was a man who had spent two nights at his brother's home in the estate.
The inquiry said droplets from his contaminated faeces then travelled through interconnected sewage pipes into faulty bathroom pipes, and infected others that way.
But Mr Ng said it would have been impossible for one patient to infect so many in such a short amount of time.
Instead, he is blaming local black rats - called roof rats in Hong Kong - which have adapted to high-rise living to such an extent that they use clothes lines to scuttle from building to building.
Rat Number 1, Mr Ng wrote, could have picked up the virus from infected material from the established first patient, before passing it on to other rats.
They, in their turn, would have carried Sars to other households, depositing the virus in their droppings or saliva.
Mr Ng says the theory needs further exploration, but maintains that it is still a strong possibility.
No guarantees
The BBC's Francis Marcus in Shanghai says that for most people in China Sars is now a memory, not yet distant, but put aside with relief.
There have been reports of the corona virus which causes Sars being found in animals such as the civet cat.
But after months of investigations, experts are still not sure where the disease originated and they fear it could return.
The fact that the group of international experts has begun a mission to probe the origins of the disease underlines how little we know about it, our correspondent says.
The scientists will try to establish ways in which Sars may be linked to animal populations despite numerous studies already showing its presence in various species.
A group of international experts is in the southern Chinese province of Guangdong to study links between animals and the pneumonia-like illness, Sars.
The experts, including World Health Organisation scientists, are visiting livestock farms, markets and restaurants in the province, which is where the disease is believed to have started.
There have been reports of the corona virus, which caused Sars, being found in animals such as the civet cat.
But scientists say they are still not sure where it came from, and they fear the virus could return. More than 800 people have died of Sars worldwide.
The scientist who identified the gene code that makes up the deadly Sars virus has been honoured by his home town.
Dr Steven Jones' team was the first to decipher the genetic code of the corona virus that has killed more than 800 people world-wide.
The breakthrough was the vital first step in allowing other scientists to find drugs or a vaccine to fight the disease.
Now Dr Jones' work has been recognised by the town of Lampeter, in mid Wales, where he grew up.
| Scientists are very competitive but when you have a major crisis we have to work together for the good of everyone
Dr Steven Jones, scientist
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He was presented with a town plaque on Thursday night by Mayor Hag Harris for his work in cracking the Sars' genetic code.
More than 800 people have died of Sars - Severe Acute Respiratory Syndrome - since the outbreak started last November.
Pure virus
After the initial outbreak in Asia, it spread to Canada, where Dr Jones, 34, works at the Michael Smith Genome Sciences Centre in Vancouver.
In April the centre received a millionth of a gram of purified genetic material of the virus taken from a Sars victim.
A group of more than 50 scientists, led by Dr Jones, then worked around the clock using state-of-the-art machines to identify the Sars genome.
And at 4am on 13 April, data coming out of the machines revealed a pure virus sequence which allowed Dr Jones' team to crack the Sars code.
Thousands have been affected by the Sars virus
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"At the time people feared the virus comprised a mutated virus combining with another one, said Dr Jones.
"But to everyone's surprise we found we had identified a new kind of corona virus."
"After double-checking the results we put our findings up on the internet. It really was a phenomenal day."
Dr Jones' group beat off competition from 13 other science teams from around the world who were also trying to crack the code.
He said: "Scientists are very competitive but when you have a major crisis we have to work together for the good of everyone,"
Dr Jones describes his achievement as the highlight of his career so far.
Although born in Haverfordwest, Dr Jones moved with his family to the Lampeter area when he was nine.
Dr Jones' parents are proud of their son's achievements
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After studying at the local comprehensive school, where he was deputy head boy, he graduated from Bristol University before studying for an MSc in genetics in Vancouver.
While taking part in a conference in Wisconsin, Dr Jones was approached by Sir John Sulston, who asked him to do his PhD at Cambridge University's Sanger Centre.
During his time there, Dr Jones worked with the group that cracked the human genome and led to Sir John Sulston receiving the Nobel Prize for Medicine last year.
World leader
But after completing his doctoral thesis, in 1999 Dr Jones was poached by another Nobel Prize winner, Michael Smith, to work at his cancer research centre in Vancouver.
"We've established a strong reputation in cancer research and we now have phenomenal resources to study the genetics of this disease which happens when cells mutate as we age," said Dr Jones, who will spend the next week at the Pentrebach farm run by his parents, John and Olivia.
Mayor Hag Harris said: "The people of Lampeter are very proud that a local lad educated at Lampeter has gone on to such success.
"His achievement in breaking the Sars genetic code was truly remarkable.".
Dr Jones' parents are proud of their son's achievements.
"Initially Steven wanted to be a vet but he changed his mind and he is now the world leader in his field," said Mr Jones
"Steven was fascinated by science from an early age and I remember him going on a school trip to Aberystwyth's biochemistry department when he was 12," said Mrs Jones.
"His teacher, Roy Evans told me that Steven wouldn't stop asking questions the whole time he was there."
The source of the virus which causes Sars may never be found, according to the World Health Organization.
Experts are discussing the possible origins of the corona virus responsible for the majority of Sars cases at the first ever global conference on the disease in Malaysia.
The current Sars outbreak has been contained and many doctors will now be looking at trying to eradicate the disease for good.
But to do this, they need to find where the Corona virus, which is known to cause Sars, came from.
The most popular theory at present is that it was passed on to humans from animals in the Guandong region of China.
Dr David Heymann, the director of communicable diseases at the WHO, says the virus has been found in both farm and domestic animals.
"The civit cat may have just accidentally picked this up in a market where it was stored with other live animals," he said.
"There are many, many possibilities. Or it may be that the civit cat picked it up from something in the environment."
Many questions
Heymann: More research needed
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"It's possible that it went the other way. If there were human faeces which contained the virus and an animal was close to those human faeces, it could pick it up from the environment," he theorised.
"So there are many questions. Each study advances the knowledge a little bit more.
"Now there must be systematic testing of hypotheses as to what might be the cause and then testing to see whether this is the case," he said.
Finding the origin of Severe Acute Respiratory Syndrome may be impossible.
At best it will take many months, but more likely years.
The good news is, though, that currently the disease is under control despite doctors not having drugs or a vaccine to protect against it.
The WHO says the outbreak highlights how new deadly microbes can spread quickly around the world, and should act as a wake-up call to the very real danger of emerging diseases.
The mystery virus which has claimed the lives of more than 150 people worldwide is a new form of the common cold, scientists have confirmed.
The World Health Organization said tests prove severe acute respiratory syndrome (Sars) is a mutant form of the corona virus, the cause of the common cold.
Officials at WHO hailed the discovery, saying it will allow scientists to concentrate on developing treatments and a potential cure for the deadly disease.
Sars has affected over 3,000 people in more than 20 countries around the world.
Scientific confirmation
These latest tests were carried out by scientists at Erasmus University in Rotterdam, Netherlands.
They are one of 13 laboratories from 10 countries working with the WHO to combat the virus.
The scientists infected monkeys with the strain of the corona virus suspected of causing Sars.
| We now know with certainty what causes Sars
Dr David Heymann, WHO
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They found that the animals developed the same symptoms of the disease as humans. The test was a crucial step in verifying the cause of the disease.
Although experts have thought that a new strain of the corona virus was the main cause of Sars, it has remained unclear whether infection with a second type of virus, the human metapneumovirus, makes the illness worse.
Their tests were made possible by studies published last week, which suggested Sars was a new virus.
Scientists from eight countries, including Germany and the United States, found it was not consistent with any other known virus.
They also carried out genetic tests on the virus, which found it was "only distantly related" to known corona viruses.
How Severe Acute Respiratory Syndrome has spread around the world
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SARS guide
Dr David Heymann, executive director of WHO communicable diseases programmes, hailed scientists' efforts to identify the virus.
"The pace of Sars research has been astounding," he said. "Because of an extraordinary collaboration among laboratories from countries around the world, we now know with certainty what causes Sars."
Dr Heymann said the discovery would now enable scientists to concentrate on developing diagnoses kits and treatments.
"Now we can move away from methods like isolation and quarantines and move aggressively towards modern intervention strategies including specific treatments and eventually vaccination.
"With the establishment of the causative agent, we are a crucial step closer," he said.
'New to science'
The discovery will also help scientists trace the evolution of Sars and could help them determine whether it jumped from animals to humans.
Tests are ongoing in pigs and poultry to see how susceptible those animals are to Sars.
Researchers at the University of Hong Kong said a new genetic sequencing of the Sars virus proves conclusively that it came from animals.
Malik Peiris, a microbiologist at the university, described Sars as "something that is new to science".
He also dismissed claims that it could have been spread by terrorists.
"That whole genome is essentially new," he said. "Nature has been the terrorist throwing up this virus."
On Tuesday, a German biotechnology company said it was distributing a new high-speed test for Sars.
Their test identifies this strain of the corona virus which has now been confirmed as causing Sars.
The firm Artus is confident the test can confirm the presence of the lethal respiratory disease in two hours, whereas traditional tests for antibodies take more than 10 days.
Sumber : internet
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