SARS sources widen

[Guest guest]

ARTICLE FROM NATURE

 

SARS sources widen

Labs brace for disease comeback.

30 October 2003

HELEN PEARSON

A new study has heightened fears that severe acute respiratory syndrome

(SARS) could hit back this winter. The pool of animals harbouring the

lethal virus may be bigger than first realized, researchers warn.

 

SARS is thought to have jumped to humans in the live-animal marketplaces

of Guangdong, China, last year. It raced round the world, claiming more

than 770 lives, before public-health officials stamped it out.

 

Now teams in the Netherlands and Hong Kong have found that the SARS

virus, which is a new type of coronavirus, infects domestic cats and

ferrets, even though the two species are distantly related. It also

scuttles into healthy animals from sick ones1.

 

The SARS virus' promiscuity implies that it may be lurking in a

menagerie of wild or domestic animals - and might readily jump into

humans again. It will also make the source of an outbreak more difficult

to track and contain. " It could be much, much harder than we thought, "

says Dick Thompson, a communications officer with the World Health

Organization (WHO) in Geneva, Switzerland.

 

The study lengthens the list of animals that carry the SARS virus - it

includes masked palm civets, raccoon dogs and ferret badgers from a

Guangdong market. Cats in the Amoy Gardens apartment block in Hong Kong,

where a rash of residents caught SARS, were also infected.

 

Red alert

 

Worldwide hospitals and laboratories are on red alert for a whiff of

SARS. " We have to be prepared for this virus to strike back, " says

Albert Osterhaus of Erasmus Medical Centre in Rotterdam, who led the

latest study.

 

Many experts predict that the virus, like those that cause some colds

and influenza, might rear up again as winter approaches in the Northern

Hemisphere.

 

SARS could materialize by several routes: a second leap from wild

animals, a jump from animals infected by humans - or an escape from one

of the many labs that are growing and studying the virus. A Singapore

lab worker was infected this way in September.

 

A cluster of patients with pneumonia-like illness should ring alarm

bells, explains Thompson. He believes that countries that were

previously affected will quickly squelch out SARS with tough

public-health measures such as patient isolation. They know how damaging

an outbreak can be, he says.

 

Test case

 

A key problem for hospitals facing a suspected SARS patient is the lack

of a reliable diagnostic test. This is one of the research priorities

identified by the WHO's SARS Scientific Research Advisory Committee, a

panel of more than 30 researchers who met for the first time last week.

 

Only if the third level comes back positive would we consider we have a

case of SARS

Dick Thompson, WHO

 

 

 

To avoid crying wolf, the experts recommended that suspected SARS

patients be tested at least three times: with two different tests and

then again by an external lab. " Only if the third level comes back

positive would we consider we have a case of SARS, " says Thompson.

 

Should a case be diagnosed, doctors still have little in the medicine

cabinet. Researchers hope that the infected ferrets, which mimic the

symptoms of the human lung disease, should prove better for testing

drugs and vaccines than the monkeys that have been available so far.

" It's much, much easier now, " says coronavirus researcher Peter Rottier

of the University of Utrecht in the Netherlands.

 

 

References

Martina, B. E. E. et al. SARS infection of cats and ferrets. Nature,

425, 915, (2003). |Article|

 

 

 

 

 

 

--

Dave Neale

Animals Asia Foundation

 

Find out more about the historic China Bear Rescue by visiting the

Animals Asia Foundation website at http://www.animalsasia.org