Levels of flu vaccinations across Britain are woefully inadequate, partly because GPs and hospital doctors are not pushing the vaccine enough, according to Leicester University expert Karl Nicholson.
Dr Nicholson, senior lecturer in infectious diseases at Leicester's department of microbiology and immunology, is chairman of the Government's advisory committee on flu, which makes annual recommendations on which groups of the population should be immunised.
He estimates that there may be 10 million high-risk people, including the elderly, people with underlying heart disease or respiratory problems, and people with diabetes or kidney disorders, but adds that thousands of the 4.5 million vaccines may be given to "worried wells" who are not high-risk.
Studies of patients with heart and lung disease, and severe diabetes revealed that barely half had been immunised, he said.
Some doctors believed the vaccine did not offer much protection, Dr Nicholson said, but he is currently heading a Department of Health study on its efficacy.
"We know that in healthy people, it provides 70 to 80 per cent protection, but perhaps less in vulnerable groups. But there is very clear and strong evidence from major studies in the United States that it is protective to people over 65, and it is also very cost effective."
Flu epidemics cause a very sharp increase in the number of deaths among elderly people, and among people with chronic underlying diseases, but the American studies show the vaccine cuts hospital admissions, and deaths from respiratory conditions by between 40 and 50 per cent.
At present, GPs themselves have to buy in the vaccine, which is manufactured on an annual basis, and Dr Nicholson said there could be a temptation to dispense it as quickly as possible to people who wanted it, whether or not they were high risk.
"If GPs had a target and payment for achieving it, that might be a better system than at the moment, which is pretty ad hoc."
Continuing medical education had a role to play in encouraging a greater commitment to vaccination among GPs and hospital doctors. Hospital staff tended to see it as a matter for GPs, but they could remind high risk patients in wards or clinics to visit their doctor. Charities concerned with the relevant diseases could also help to educate the public, Dr Nicholson said.
He urged people in high risk groups to seek vaccination now.
"Influenza can circulate at any time, but typically around Christmas. It's important to immunise people as early as possible."