Health experts, talking at a London press conference, have stressed that the H1N! virus, commonly known as swine flu, could return to the UK with a bang.

The public perception in the UK is that everyone has already either had swine flu and that those that haven't have had the vaccine to combat it. However, experts say this isn't the case. While some UK areas saw large numbers of people contracting the swine flu virus (up to 40 percent of school children in some areas), other areas in the UK were largely unaffected.

The real threat, say health care experts, is that the H1N1 virus could return next winter and hit hard those people who didn't take the swine flu vaccine in the winter of 2009 or didn't contract the virus the first time around.

GlaxoSmithKline (GSK), which makes the Pandemrix swine flu vaccine, estimates more than 42 million people in Europe have had one of three main vaccines for the virus. Yet with over 60 million people living in United Kingdom it is obvious that there is a large swathe of the public that hasn't had any vaccine to combat this very virulent disease.