Posted on 05/08/2003 8:29:58 AM PDT by EternalHope
SARS may be here to stay say researchers 08/05/2003 - 15:28:14
SARS may be here to stay after making itself at home in the human population, new research suggested today.
A study showed that the virus behind Severe Acute Respiratory Syndrome is not likely to mutate into a less dangerous form in the foreseeable future.
Similar viruses that have caused serious influenza epidemics in the past have eventually ceased to be a threat after changing their DNA.
But the evidence indicates that SARS is genetically settled and in no hurry to alter form.
This is bad news for public health, since it means the virus is likely to stay active and dangerous for a long time.
SARS is triggered by a strain of coronavirus not seen before in humans, given the label SARS-CoV.
Human coronaviruses are one of the main causes of the common cold, but normally only produce mild symptoms.
They belong to a family of RNA viruses known to have a high rate of genetic mutation which can lead to new strains.
Researchers led by Edison Liu, from Singapore’s Genome Institute, studied the genetic make-up of cultured SARS viruses from five different sources.
They found only a handful of mutation differences between the isolates, and it was thought these probably resulted from the virus adapting to laboratory conditions.
The findings were published in an on-line report from the Lancet medical journal.
In an accompanying commentary, two Canadian experts warned of the implications.
Early Brown and Jason Tetro, from the University of Ottawa, said: “The results suggest a remarkable genetic conservation of the virus since the outbreak was first documented in February 2003..
“It can.. be concluded that as the virus passes through human beings, SARS-CoV is maintaining its consensus genotype and is thus well adapted to the human host.
“Unfortunately, this conclusion means that SARS-CoV is not likely to change rapidly and thus may not readily mutate to a benign infection, as is the hoped-for eventuality seen in most other epidemics.”
Another SARS study reported in the Lancet provides a frightening picture of what the virus does to its victims.
Researchers monitored 75 patients caught in an outbreak of SARS at Amoy Garden, a Hong Kong high-rise housing estate.
The source of the outbreak in March was thought to be a faulty sewage system initially contaminated by excreta from an infected visitor.
Despite being given standard treatments of antiviral agent and corticosteroids, most patients showed a similar pattern of worsening illness.
Symptoms improved throughout the first week of hospital admission, but got worse in the second week.
Fever and pneumonia initially improved but 85% of patients developed recurrent fever after nine days.
After one week in hospital, 73% had watery diarrhoea and 80% had X-rays suggesting worsening lung condition.
Just under half the patients had reduced respiratory function after 8.6 days, and 45% who had improved after initial lung damage developed lesions in different locations.
A total of 20% of patients developed a serious condition called acute respiratory distress syndrome (Ards) in the third week which required mechanical ventilation.
The researchers said it was likely the clinical deterioration seen in the second week after hospitalistion was due to an overblown immune response rather than uncontrolled spread of the virus.
Looks like they did their homework on this one. SARS is unlikely to weaken in the short/medium term.
I see no homework. I see groundless pontification for the sake of drumming up hysteria.
So key would be muting the immune response. Explains why the serum is only effective early in the course of the disease.
Then you did not actually read the article.
Independent research points to a genetic experiment and accidental release.
But I do not want to shout too loudly about the prospect of genetic engineering. Yes, I might be considered to be wearing a 'tin foil hat' . . . But it is not firmly on my head today. Everything is supposition and conjecture when people are talking about origins and causes.
This is a very dangerous bug. Keep it in China !!
Independent research points to a genetic experiment and accidental release.
But I do not want to shout too loudly about the prospect of genetic engineering. Yes, I might be considered to be wearing a 'tin foil hat' . . . But it is not firmly on my head today. Everything is supposition and conjecture when people are talking about origins and causes.
This is a very dangerous bug. Keep it in China !!
..it is not so much that scientists working with viral hybridizations were pushing nature in new directions when they ambarked on expirements in this field, but that they were following reactions that occurred in their laboratory. As J. Cookson and J. Nottingham note in their survey of Chemical and Biological Warfare, "It was observed (huebner, et al) that in tissue culture cross-infection with two different viruses may occur. This is not, by the way, evidence that such reactions occur naturally, since cultures in laboratories are highly artificial; yet it does indicate that the hybridizations do happen spontaneously. "As a result -of this combination- a virus that resembles one of the original viruses in it's protein coat (due to alterations in it's DNA) and also posseses characteristics of another virus may be produced. Such a virus could be potentially devestating to the host. Suppose a relatively benign virus to which the host was accustomed, which are tolerated by the human body, were combined with a more lethal viruse. Suppose further that it was the benign virus that provided the coat, hence the antigen markers through which the human immune system identifies intruders. Flagging this virus as an innocous character. The virus would be suitably disguised to the animal or plant it was infecting and so could wreak havoc unrecognized.
excerpted from AIDS A Second Opinion
Gary Null, Phd
On the humorous side.
I went to the link and it is gobbledy-gook... if there is someone who can restate the conclusion in simple layman's language it would be nice.. (It wasn't even in English...)
"The outbreaks are going on and increasing rapidly and we're not able to do the assessment to make sure these places are safe," said Dr. David Heymann, WHO's executive director for communicable diseases."
Doesn't look good at all!
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