Satellites study deadly dust storms

Dust storm moving across Africa
A dust storm as seen by MSG-1
10 May 2005
Dust is a great traveller. It is not uncommon for a fine coating of dust from Africa’s Sahara desert to settle on parked cars thousands of kilometres away.
But dust can be a killer. On the dry fringes of the Sahara (known as the Sahel), 300 million people are at risk from a deadly disease called meningitis.

This disease causes swelling of the brain and the lining of the spinal cord. Those it does not kill may be hit by deafness and brain damage.

"Meningitis outbreaks take place after a period without rain, low humidity and lots of dust in the air," explained Isabelle Jeanne of the Centre de Recherche Médicale et Sanitaire in Niger.
Marocco and Canary Islands, 1 March 2003
Dust blown from the Western Sahara towards the Canary Islands
The exact link is not yet known. One theory is that wind-blown dust, as fine as talcum powder, causes irritation inside people’s noses. This makes it easier for bacteria to enter the blood stream.

ESA is helping scientists to study and predict outbreaks of meningitis. The aim is to learn more about the lethal epidemics that often follow the dust's arrival.

Medical researchers are using satellite images to track massive dust storms that sweep across the Sahel. During the last dry season, ESA supplied weekly dust maps as part of an early warning system. The Sahel maps are based on daily images from the ESA-built Meteosat-7 weather satellite.

The next step is to study images taken over the last 10 years and search for links between dust storms and outbreaks of the disease.

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