Quick Diagnosis for Early Treatment

If you're getting your child tested for strep throat, it usually takes just minutes to get the results back. But in most cases, it takes days to weeks to find out which microorganism is making someone sick. We can't depend on symptoms because many infections resemble the flu.

That's why scientists are developing a new generation of biosensors to do this job within hours so treatment can begin immediately. Right now we depend on a one hundred fifty year old method which takes a patient's sample and grows it in a dish so it can be identified.

But viruses, fungi, and parasites tend to be much harder to grow, isolate and identify. Plus, many infectious agents can't be isolated in the lab at all. That's why we need a much better diagnostic tool.

The new method uses two advanced technologies. One is a mass spectrometer which identifies a pathogen based on the mass of a unique piece of its genome. The challenge is finding it among the patient's own massive amounts of DNA and RNA.

The solution is to pair the spectrometer with PCR or polymerase chain reaction which amplifies many copies of the targeted genomic sequence. Thus, once the PCR amplifies pieces of potential pathogen genomes in the sample, the mass spectrometer spits out a series of numbers that can then be cross-referenced to a database of over a thousand pathogens that cause human disease. This can be accomplished in just a few hours.

A prototype of the sensor was used in 2009 to identify two kids with the H1N1 flu virus which at the time was new. The new sensor has the potential to become a universal pathogen detector.