Threatwatch is your early warning system for global dangers, from nuclear peril to deadly viral outbreaks. Debora MacKenzie highlights the threats to civilisation ? and suggests solutions
It's one of those stories where bemused interviewers ask, how worried should we be? Two people from the Arabian peninsula picked up a virus no one has ever seen before; one is now very ill, the other has died. The virus belongs to the same family as SARS, another virus no one had seen before when it emerged from China in 2002.
SARS circled the globe and killed almost 800 people, and those are just the ones we know of. Were it not for a landmark global effort in disease control ? and a fair amount of luck ? it would probably still be out there. Is the still-nameless Middle Eastern virus the next SARS?
No it isn't ? yet. But this column is about watching for threats, so we can protect ourselves. And this story is exactly that. We know about this virus solely because of a European Union project set up in response to SARS. It funds scientists to monitor unusual infections ? and spot the next SARS, or whatever, before it's crawling through city tower blocks and international airports.
"If we had known about SARS when it had only infected a few people, we might have stopped it then," says Ab Osterhaus of Erasmus Medical Center in Rotterdam, the Netherlands, who helped set up the system.
Case histories
A 60-year-old Saudi man died in July of pneumonia plus kidney failure. Doctors there sent samples to Ron Fouchier at Erasmus, who caused a storm last year with work that made H5N1 bird flu virus transmissible among mammals.
A man from Qatar with the same symptoms was flown to London for intensive care in September. Rotterdam asked for a sample. Preliminary sequencing suggests both men were infected by the same new virus, says Osterhaus.
The technology now available for sequencing whole viruses within days means new human respiratory viruses are being discovered at the rate of about one per year, says John Oxford of Queen Mary College in London. But sequencing is too expensive to routinely screen every unexplained illness ? without help.
"It's like stamp collecting," says Osterhaus. "You don't know when something is going to turn out to be interesting," so ordinary research funding doesn't cover it. Neither the Saudi nor the Qatar sample would have been sequenced, he says, without the European Union's EMPERIE programme, set up after SARS to watch for novel viruses with the aim of catching the next epidemic before it gets out of control.
"It gives us a whole virus discovery machine," says Osterhaus, from screening bats, to sequencing samples from humans, to alerting medics to watch for odd cases. Now they know this family of coronaviruses can kill people, they also know to handle it at safer levels of containment.
Poor transmission
To be the next SARS, the virus has to be transmissible among people, and none of the people who have come into contact with the men, including hospital staff, show any sign of infection. But now that they know what to look for, the Dutch lab and collaborators in the Middle East are testing samples kept from recent pneumonia cases in the region, and the World Health Organization has issued an alert for new cases.
The sequence shows it is not very closely related to SARS, says Osterhaus, although it is from the same subfamily of coronaviruses that is common in bats. "It could be spreading at very low levels in the Middle East, but mostly causing mild disease we don't see. Or it could be only occasionally spilling over into people from bats."
Either way, it will be one more virus that is being watched. "Any evidence of human-to-human transmission causing severe disease would be very worrying," says Peter Openshaw, head of the Centre for Respiratory Infection at Imperial College London. The patients so far could just be unusually severe cases of a generally mild infection, he hopes, and we are picking up the new virus simply because our surveillance has improved.
But that's what watching for threats is all about.
If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.
Have your say
Only subscribers may leave comments on this article. Please log in.
Only personal subscribers may leave comments on this article
Subscribe now to comment.
All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.
If you are having a technical problem posting a comment, please contact technical support.
Colorado shootings dark knight rises Aurora shooting James Eagan Holmes anne hathaway klimt bastille day
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.