Chip test quick for bird flu

29-08-2006 | |

Scientists have developed a detailed influenza test that takes less than 12 hours to provide a result, speeding up the diagnosis of the most dangerous avian flu, according to US federal health officials.

The new technology is a microchip covered with bits of genetic material from many different flu strains. Using the chip cuts diagnosis time from a week or more to less than a day, and it usually reveals which flu an animal or person has, rather than a simple positive or negative result.

That means that public health officials investigating a flu outbreak in poultry or in humans will be able to decide quickly whether to kill thousands of birds or to treat hundreds of potentially exposed people with expensive anti-viral drugs.

Right now, ascertaining whether bird flu is of the lethal H5N1 strain requires that a sample be frozen and shipped to a highly secure laboratory, of which there are few, where the virus can be grown in eggs, isolated and genetically sequenced, a process that takes four to five days plus shipping time.

The new test, called FluChip, can be performed in any laboratory that can amplify bits of genetic material; many countries have such laboratories in their national capitals. Samples need not be frozen, and because only bits of genetic material are multiplied rather than whole viruses, the work can be done in laboratories with lower biosecurity levels.

Nancy J Cox, chief of the influenza branch of the Centers for Disease Control and Prevention in Atlanta, said the chip “really allows us to get a lot of information about a virus in a short time”.

Dr Anthony S Fauci, director of the National Institute of Allergy and Infectious Diseases, which announced the creation of the test, called it an “encouraging advance” that could be “invaluable to international flu surveillance efforts”.

A more advanced version may be ready within two years, said Kathy L Rowlen, the University of Colorado chemistry professor who led the team that developed the test.