Did last year’s flu jab open the door to swine flu?

The return of swine flu seems to have taken the health authorities by complete surprise – witness the Government's less than elegant U-turn on reinstating the 'Catch it, Bin it, Kill it' advertising campaign.

Numbers of flu victims were rising steadily through the last weeks of 2010. But it isn't just a question of statistics that is now beginning to worry some of Britain's most accomplished virologists – there's also a mystery which could have profound implications beyond the present epidemic.

Some doctors have spotted that an unusual group in the population has been hit particularly hard by the present outbreak. As one senior virologist put it just before Christmas, "They're the aspirational, professional young middle-aged. They're the sort of people who would have probably had the flu jab the last time round – in order to keep on working, come what may."

The question he and colleagues are now urgently asking is whether last year's jab could have made them more vulnerable to this year's attack by the H1N1 swine flu virus.
 
"The injection last year could have allowed the current strain an ‘easy entry' to the patient's system in this outbreak," my source said. "Of course, this is a very delicate issue – and could have huge implications for the whole national immunisation strategy."

By the end of last week, the number of swine flu sufferers in intensive care had reached 738, after doubling every week. As the Daily Telegraph reported at the weekend, vital cancer operations have had to be cancelled to leave enough beds free in Britain's hospitals.

Currently 16 million people in Britain are believed to be at risk of catching the virus, which is understood to be spreading at twice the rate as in the major flu outbreak of 1999 – 2000.

Pandemics are now high on the agenda of major strategic threats to advanced societies like those of Britain, America and Europe. They feature in third place in the top tier of risks facing the country in the government's National Security Strategy announced by William Hague last October.

Doctors and security planners have feared a major flu pandemic for years. In the bird flu outbreak which began in Asia five years ago, more than half of all human victims died.

The Chief Medical Officer of the day, Sir Liam Donaldson, has estimated that a serious outbreak of avian flu could kill 65,000 in Britain. According to one study presented to the Joint Services Staff College, a serious bird flu outbreak would knock out nearly 40 per cent of all health professionals - doctors, nurses and paramedics - in the first 10 days.

Most terrible of all outbreaks in modern times was the 1919 Spanish flu pandemic that killed more than the number who had died on the battlefield in all four years of the First World War in Europe. In total, that pandemic killed 50 million worldwide.
 
Already swine flu is spreading faster in the UK than in neighbouring Europe. The bad news is that the figures are likely to climb even more steeply when children return to school in the coming days. ·