A POTENTIALLY deadly fungus which poses a major danger to patients undergoing surgery such as transplants has been unravelled for the first time by researchers in Aberdeen.

Scientists have discovered how the immune system recognises the fungus, known as Aspergillus fumigatus. They hope this will lead to new drugs able to combat the infection.

The fungus kills around 200,000 people worldwide every year and causes lung and allergic diseases in millions of others.

It is one of the most feared complications for patients undergoing treatments such as transplantation as it can lead to an invasive infection that is fatal in more than half of cases.

Humans breathe in hundreds of aspergillus spores every day as they are emitted from household items such as garden compost.

For most healthy people, the spores do not lead to disease but for those with compromised immune systems it can be deadly.

The fungus is so effective because it is very difficult to diagnose and treat.

Now a study by medical researchers at Aberdeen University, published in the journal Nature, has shed light on how the immune system responds to the microorganism.

They found that it recognises a specific pigment in the fungi called melanin. This is unusual because it was previously thought that the immune system primarily recognised sugars in the cell wall of fungi.

They also discovered variations between individuals' immune systems that make some more susceptible to infection if they are undergoing medical procedures such as transplantation.

It is hoped that this finding will shape the development of new diagnostic tools and drugs to help combat these infections.

Professor Gordon Brown, Director of the MRC Centre for Medical Mycology at the University of Aberdeen says: “This is a fungus that most of us come into contact with on a daily basis without consequence. However, for vulnerable people undergoing serious medical interventions, it can be fatal.

"Understanding how our immune system responds to this invader is crucial to improving our ability to identify its presence in infected people and to develop therapies to help us treat this disease."