BACKGROUND: Scientists at the University of Colorado, Boulder, have developed a new flu-detector chip that can quickly determine the genetic signatures of specific influenza strains in samples taken from patients. The analysis can be completed within 11 hours, compared to other tests that take four days. While existing commercial rapid tests can detect the presence of influenza within an hour, those don't provide useful genetic information for identifying strains. The chip could also be easily reconfigured to test for the avian flu virus, as well as any other virus whose genes are encoded as RNA instead of DNA -- including SARS, measles, HIV and hepatitis C.
HOW IT WORKS: The flu chip fits on a standard microscopic slide and has rows of dots -- five in all, with three dots in each -- containing a specific sequence of DNA. During processing, RNA fragments from a "wash" of influenza gene fragments taken from a patient binds to specific DNA segments to indicate a match, much like a key perfectly fitting a lock. That RNA is then labeled with another DNA sequence containing a fluorescent dye that lights up when the chip is inserted into a laser scanner. The chip is currently about 90 percent accurate and is now being tested against standard testing methods used by the Center for Disease Control and Prevention. The Boulder scientists hope to make the process even faster by amplifying the telltale fluorescent signal, thereby shortening the test to as little as two hours. They also hope to downsize the technology into a handheld portable device the size of a cell phone or PDA.
PANDEMIC PANIC: Being able to determine the specific influenza strain in a sample may help world health officials combat future flu epidemics and pandemics. Strain identification is critical for tracking emerging strains and determining which flu strains are most likely to infect the population the following year in order to develop annual preventive vaccines. Historically, flu pandemics occur when a new strain of the flu virus emerges that is particularly contagious. They can cause millions of deaths worldwide, ranking a flu pandemic among the top four global risks listed by the World Economic Forum.
The American Meteorological Society contributed to the information contained in the TV portion of this report.