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Wednesday, 18 September 2013

'Flu update

It's that time of year again. Doctors are planning their 'flu vaccine clinics and posters are appearing reminding us to get our annual dose. Since last year there have been several interesting new developments in ‘flu research.
Over a hundred cases of H7N9 'flu in humans, probably contracted from poultry, have been seen in China. The high death rate emphasises the importance of influenza research. It's a race against time before a variant emerges that can easily be transmitted between humans. When it does it could cause a lethal pandemic with catastrophic death rates.
Even the usual winter 'flu sometimes causes serious illness and up to half a million people die of it, every year.
Some of this year's new information is based on analysis of existing data.
A systematic review of a large number of studies highlighted that new mums (but not pregnant ones) and obese individuals seem to be at an increased risk of dying of the complications of 'flu. These two risk groups have not been previously identified. Good quality research in this area is rather thin and more is needed so vaccination programmes can be targeted appropriately.
Another analysis found that in the 2009 outbreak of swine 'flu, pregnant women who had been vaccinated were less likely to go into premature labour than the non-vaccinated. It seems then that 'flu vaccines during pregnancy may protect both babies, from the dangers of being born too soon and mums from becoming seriously ill with 'flu, or even dying, in the month following delivery.
An Australian study looked at links between heart attacks and 'flu, using data on middle-aged people admitted to hospital. It found that having a 'flu vaccination seemed to have a protective effect against heart attacks. If other research confirmed this result it would, again, lead to a change in the recommendations for priority groups.
One of the most interesting, and surprising, findings of the year is that 'flu vaccines are not as specific as everyone thought. Immunology theory is clear - that the immune system develops antibodies, one virus at a time. So every variant of the virus requires a vaccine to match it. Each year the vaccine is a cocktail of the three types that are currently most common worldwide. This new study found that the vaccine gives significant protection against types of 'flu that are not included as well as those that are. This highlights the fact that there is a lot more to the immune system than just antibodies - and that there is still a great deal to learn about how it works.
Finally, for the needle-shy, there is hope on the horizon. Nasal spray 'flu vaccines are being introduced, (initially for use with children in the UK) and research on mice has revealed that a micro-needle patch can deliver 'flu vaccine effectively. I imagine this would be a bit like pressing a bit of Velcro or sandpaper against your skin.
In the UK the 'flu vaccine is free to priority groups and the rest of us have to pay. I always think that £10 spent on a 'flu jab is fantastically good value if it means I can get through another winter without a bout of this debilitating illness.

New risk groups

Vaccine in pregnancy

Heart attacks

Wider protection

Micro patches