WHEN a disease outbreak is confirmed, it is a race against time to find the source and control its spread. Technology that can rapidly sequence bacterial genomes could help, now it has been successfully deployed during an outbreak.
On 15 July 2011, a 43-year-old woman was discharged from the National Institutes of Health Clinical Center - a research hospital in Bethesda, Maryland - following treatment for a drug-resistant strain of Klebsiella pneumoniae. Three weeks later, despite a rigorous quarantine procedure, hospital staff discovered a second case. To head off a potential outbreak, the staff needed to find out quickly whether the cases were related.
Traditional ways of genetically analysing infections, such as pulsed-field gel electrophoresis, were too crude to provide an answer.
So Julia Segre of the US National Human Genome Research Institute and her colleagues decided to do whole-genome sequencing on the strains, which can be completed for small genomes in just a few days.
Hospital staff could then work out genetic similarities between the bacteria infecting different people - information that helped to establish exactly how the infection was spreading. The approach enabled Segre's team to identify and eradicate transmission paths. For instance, plumbing in hospital sinks was replaced (Science Translational Medicine, doi.org/h7r).
The infection affected 18 patients, 11 of whom died, before it was brought under control. It could have been much worse, though. Sharon Peacock, a clinical microbiologist at the University of Cambridge, is impressed. She has previously advocated genome sequencing for outbreak control. "It's going to lead to a step change," she says.
Automating the process could also make it suitable for more generalist hospitals, she adds.
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