Four million people die every year from respiratory diseases such as viral influenza. For elderly people in particular, an infection can be dangerous. What is more, the flu vaccine is not as effective with this risk group as it is with younger people. The reason for this is that with age the fire power of the immune system is reduced. Why this is the case is largely unknown. An international EU project led by the University of Bonn is now starting which aims at shedding light on this. Among other things, the researchers want to get a step closer to solving this riddle by examining tens of thousands of blood samples. The objective is also to develop new medicines which largely inactivate the viruses and enable the immune system to deal with the small amount of residual viruses.
Spanish flu took the lives of at least 25 million people between 1918 and 1920. But the disease was not only exceptional because of its extreme virulence. The patho-gen, the influenza virus subtype A/H1N1, homed in on women and men in the prime of their lives. 'Normally respiratory diseases are dangerous for children and the over-60s,' the project coordinator Dr. Oliver Schildgen explains. 'What's more, in the case of the elderly the flu vaccine unfortunately only prevents the disease in six out of ten cases.' By contrast, with young adults, the success rate is as high as 90 per cent.
The reason for this is that the effectiveness of the immune system decreases with age. An international research consortium now wants to find out why this is the case. Roughly 1.8 million euros will be provided by the EU for this in the next three years. With other diseases it has already been proven that the older body can no longer produce a sufficient amount of effective antibodies. 'We want to know in particular whether this is the case with infectious diseases where the viruses were discovered recently,' Oliver Schildgen says.
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