Deaths support extension of swine flu vaccination to wider population, says NHS chief
By Gareth Iacobucci
The swine flu pandemic is ‘considerably less lethal' than originally feared, but the mortality rate in healthy people supports an extension of the vaccination programme to the general population, according to the Chief Medical Officer.
The new figures oublished online by the BMJ, show there were 26 deaths out of every 100,000 cases of swine flu in England - a fatality rate of 0.026%.
The study by Sir Liam Donaldson's team concluded that the pandemic is ‘considerably less lethal than was feared in advance', but warned 40% of deaths were in previously healthy people and there was 'a case' for extending swine flu vaccination to everyone.
The mortality figures were from PCTs and acute hospitals, who were asked to collate data on individuals who were believed to have died from swine flu between June and November 2009.
They reveal over two thirds of the patients who died from swine flu would now be eligible for vaccination, which - the authors say - demonstrates the importance of vaccinating high risk groups.
Researchers also argued the case for extending the vaccination programme and making antiviral treatment available to the wider population, as 38% of deaths occurred in non-high risk groups, despite recent research that showed Tamiflu had only 'modest effectiveness' against the complications of swine flu.
'Given that a substantial minority of deaths occur in previously healthy people, there is a case for extending the vaccination programme and for continuing to make early antiviral treatment widely available,' the paper says.
The study also revealed that over 65's had less chance of contracting swine flu, but were more likely to die from the disease if they developed it.
The authors argue that the reduced chances of over 65s contracting swine flu may be because they had already been exposed to similar strains and that: ‘without this previous exposure, the pandemic might have caused many more deaths in this age group.'
The researchers say their estimates of fatality rates compares favourably with the other three 20th century influenza pandemics – the rate for the 1918 Spanish flu was 2-3% and subsequent pandemics (1957-8 and 1967-8) had rates of around 0.2%.
Sir Liam said the apparent decrease in case fatality from one pandemic to the next could be explained by ‘improvements in nutritional status, housing and health care availability, and major advances in intensive care medicine.'
The authors conclude: ‘Many more patients may have died in England without the ready availability of critical care support, including mechanical ventilation.'DH