SAN FRANCISCO, Oct 24, 2004 (United Press International via COMTEX) -- As Americans scramble for scarce doses of flu vaccine, a new strain of the respiratory bug is emerging, the San Francisco Chronicle reported Sunday.

The new A/Wellington, named for the New Zealand city where the strain first turned up, can diminish the effectiveness of today's vaccine.

Contamination problems were found at a Chiron Corp. factory in Liverpool, England, effectively wiping out about half the United States supply.

Officials said last week they are optimistic that those who get flu shots will be protected, but the new strain is showing signs that it resists the current flu vaccine.

World Health Organization epidemiologists who track the ever-evolving strains of influenza say the predominant flu virus around the globe right now is called A/Fujian.

While the vaccine Americans are seeking now is a perfect match for A/Fujian, the new strain is gaining ground. Tests suggest that 43 percent of recent New Zealand flu cases spring from the new strain, or variants of it.

A/Wellington has turned up on the other side of the world from New Zealand, in Norway.

The WHO on Oct. 8 recommended that next year's flu vaccine for the Southern Hemisphere, which is shipped in March, be reformulated to ward off A/Wellington.

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