Anthrax Field Tests Called Unreliable

The White House is warning that anthrax field tests, widely used since last fall’s terrorist attacks, give fast but often incorrect results, prompting authorities to shut down buildings prematurely and hand out unneeded antibiotics.

In a memo being sent Monday to more than 250 federal agencies and to firefighters, police officers and local officials across the country, authorities say none of the commercially available field tests are reliable. They advise federal agencies to stop using them and to cancel any pending contracts to purchase the test kits.

The advisory comes after an extensive study of the tests by the federal Centers for Disease Control and Prevention for the FBI. The study found that all tests on the market are prone to miss small amounts of anthrax and to detect anthrax when there is none.