English 版 (精华区)
发信人: xiaozhu (XXXX), 信区: English
标 题: strange pneumonia
发信站: 哈工大紫丁香 (Wed Apr 2 22:11:15 2003) , 转信
Identity of mystery pneumonia bug sharpens
Questions raised over readiness for lethal SARS epidemic.
20 March 2003
HELEN PEARSON
Laboratories have been comparing the pathogen to known types of paramyxovirus.
© Corbis
As laboratories worldwide home in on the virus responsible for the mysterious
global outbreak of pneumonia, critics say that researchers could have been bet
ter prepared to anticipate the epidemic.
So far, 264 people worldwide are known to have been infected and 9 have been k
illed by Severe Acute Respiratory Syndrome (SARS). This flu-like condition is
characterized by high fever and breathing problems. Fears began escalating aft
er the World Health Organization put out an exceptional alert last week.
Laboratories in Hong Kong, Germany and Singapore have now found signs that the
culprit may be a new type of paramyxovirus - one of a family of viruses that
cause respiratory illnesses, measles and mumps. They examined the genetic sequ
ence of the virus and looked at its shape through an electron microscope; both
matched those of known paramyxoviruses.
Immunologists stress that it is too early to conclude that a paramyxovirus def
initely causes the lung illness - the virus could be a coincidental infection.
To be sure, the collaborating labs must find tell-tale viral RNA in all patie
nts and show that their blood contains specific antibodies against the virus.
If the labs' suspicions are correct, there are few drugs and no vaccine to fig
ht this pathogen, warns Christopher Broder, who studies paramyxoviruses at the
Uniformed Services University in Bethesda, Maryland. One drug, ribavirin, cou
ld be tried; this is used to treat the paramyxovirus that causes respiratory s
yncitial virus infection in children.
Heads up
New strains of paramyxovirus have killed humans twice before, after jumping fr
om animals. In 1994, two stable workers died in Australia having contracted a
horse strain called the Hendra virus. And in 1998, 105 Malaysian pig farmers d
ied from the related Nipah virus. In both cases, the animals were first infect
ed by fruit bats.
Events such as these have prompted some experts to ask why the latest outbreak
wasn't better anticipated. "If we had our act together we could have seen it
coming," says Donald Burke, who studies the spread of infectious diseases at J
ohn's Hopkins University in Baltimore.
If we had our act together we could have seen it coming
Donald Burke
John's Hopkins University, Baltimore
Burke argues that there has been time enough to develop more rapid diagnostic
tests to identify new strains of paramyxovirus, and to assess potential strain
s brewing in animals. "No one is doing anything approaching a systematic surve
y of paramyxovirus in other species," he laments.
These concerns are echoed in a US Institute of Medicine report co-incidentally
issued this week. Its authors - of whom Burke is one - warn that the world re
mains poorly prepared to deal with emerging pathogens. They call for more inve
stment to boost surveillance and response to potentially threatening bacteria
and viruses.
Other experts are more sanguine. Infectious-disease researcher Stephen Morse,
of Columbia University in New York City, reckons that the response to the curr
ent outbreak has been relatively swift and effective. At the start of the late
st epidemic, in February, the Hong Kong Department of Health traced seven of t
hose initially infected to the same hotel in Kowloon.
And the spread of the disease seems to have been partly stemmed by keeping sus
pected patients in isolation. So far it is mainly close family members and hos
pital workers who have been infected. Even so, the situation is "damned scary"
, concedes influenza researcher Robert Webster of St Jude's Children's Researc
h Hospital in Memphis, Tennessee.
© Nature News Service / Macmillan Magazines Ltd 2003
• Mice catch cruise-ship virus
7 March 2003
• West Nile takes new tack
16 October 2002
• Polio made from scratch
12 July 2002
• Ebola vaccine hope
30 November 2000
• CDC: SARS
• WHO: SARS
• Institute of Medicine
• Deadly virus effortlessly hops species
2 April 2003
• Maths gets into shape
2 April 2003
• Plastics spoil mouse eggs
1 April 2003
• Ancient civilization goes online
1 April 2003
--
※ 来源:.哈工大紫丁香 http://bbs.hit.edu.cn [FROM: 210.46.79.195]
Powered by KBS BBS 2.0 (http://dev.kcn.cn)
页面执行时间:3.359毫秒