The flu vaccine may only be 20 per cent effective this winter, researchers predict as the threat of a severe outbreak lies ahead.
A study found H3N2, the same strain which blighted Australia and caused an influx of cases during their winter, has mutated.
Scientists blame the 70-year-old manufacturing process of the vaccine, warning it has allowed the aggressive strain to escape detection.
Officials are concerned H3N2 will pose the same danger to Britain, as the flu season tends to mirror that of the Southern Hemisphere’s.
And experts are worried it could prove as deadly to humanity as the Hong Kong flu in 1968, which killed one million people.
The new findings, based on last year’s jab, echo the beliefs that this year’s vaccine isn’t strong enough to fight the aggressive strain.
