WASHINGTON - The Food and Drug Administration said Friday that none of the influenza vaccine made by Chiron Corp. (CHIR) is safe for use.

Acting FDA Commissioner Dr. Lester M. Crawford said the determination was made earlier Friday after the FDA completed an inspection of the company’s manufacturing plant in Liverpool, England.

Earlier this month, British authorities temporarily suspended Chiron’s manufacturing license, taking U.S. authorities by surprise. On Oct. 5, Chiron announced it wouldn’t be able to ship its planned 46 million to 48 million flu shots to the U.S.

U.S. officials dispatched an FDA team to London to meet with United Kingdom health authorities and to determine whether any of Chiron’s flu shots were usable.

In August, Chiron, of Emeryville, Calif., announced a small number of lots were contaminated with bacteria.

Dr. Crawford said the FDA couldn’t determine whether the remaining lots were safe. Dr. Crawford and other U.S. health officials had hoped some Chiron’s vaccine would be usable.

Aventis, a unit of Sanofi-Aventis (SNY), will supply 55.4 million doses of flu vaccine to the U.S. market, but that number is far short of the 100 million doses the FDA had hoped to have available this season.

In response to the flu-shot shortage, the Centers for Disease Control and Prevention pared back its recommendations to suggest that healthy children and adults ages 2-to-64 forgo a flu shot this year.

The CDC recommends that babies and toddlers ages 6-to-23 months receive a flu shot as well as those age 65 and older, pregnant women and some health-care workers. The CDC had previously recommended that everyone over age 50 receive a flu shot.

A few people in the healthy group can seek a nasal spray made by MedImmune Inc. (MEDI) of Gaithersburg, Md. That company has said it will supply between one and two million doses of its FluMist vaccine. That spray is approved for use only in healthy children and adults ages 5 to 49 years old.

Influenza typically kills 36,000 people in an average year and hospitalizes up to 200,000. It peaks in the U.S. sometime between December and March.