International airports battle malaria

By JOHN LICHFIELD

Visiting, or living near, international airports can damage your health. The hazard does not come from aircraft noise alone, nor purely from aircraft falling out of the sky.

There is also a risk of catching tropical diseases, especially malaria, from mosquitoes which have stowed away aboard intercontinental flights.

The danger has been around since air travel began. The phenomenon even has a name."Airport malaria" happens when the disease is caught by people who have never visited tropical countries but live close to, work in, or visit airports.

For 50 years or more, aircraft arriving from malaria-inflicted countries have, in theory, been sprayed with insecticides.

Nevertheless, there have been 14 such cases in Britain in the past 30 years, including seven in the past five years. In two of the British cases, severe attacks of malaria were traced to imported mosquitoes which flew up to 13km into suburban Sussex from Gatwick Airport before biting their unsuspecting victims.

There have been 26 cases in France (the worst affected country) since 1969. There have been two cases in Belgium in the past few months and a nasty outbreak in Luxembourg. There have been 100 known cases in Europe and the United States in the past 30 years, leading to six deaths.

This is hardly an epidemic. However, a lengthy report published in the bulletin of the World Health Organisation (WHO) this month points out two new factors, both man-made, which could lead to an alarming and unnecessary spread of airport malaria in coming years, unless airlines and governments tighten the rules on the anti-insect spraying of aircraft. The first problem is global-warming, which could make the temperate climates of European countries more hospitable to the survival - even the breeding - of tropical varieties of mosquito.

The second problem is a growing consumer-resistance to the spraying of insecticides inside the passenger cabins of aircraft. Several lawsuits have been brought against airlines in America and Germany, complaining that the insecticides used are dangerous to the health of humans, as well as mosquitoes.

"There is no scientific evidence whatever that this is the case. It is just an unwarranted scare," said Dr Norman Gratz, the principle author of the article in the WHO bulletin, and an expert on airport malaria.

"The problem is that the airline precautions against mosquitoes are already more haphazardly applied than they should be. This campaign against insecticides threatens to make things worse.

"Airport malaria is a serious problem. It is not yet a growing problem but it is a continuing problem and it need not be. We have all the knowledge we need to bring it under control."

The French Government has already taken tough new measures, demanding documentary guarantees that any aircraft arriving from Africa, or any malaria-affected country, has been "de-insected" before take-off.

This follows one of the worst outbreaks of airport malaria, in 1994 at, and around, Charles de Gaulle airport in Paris (which was little reported at the time).

Six people, living near or working at the airport, were infected with malaria during a three-week period. One died. Around 300 aircraft arrived from Africa in the period concerned. An official investigation estimated that up to 6000 potentially infected mosquitoes arrived in France over 20 days with many escaping into Charles de Gaulle airport and the surrounding suburbs.

An official in the French quarantine service said that the stricter restrictions on airlines had been partially, but not entirely, successful.

- INDEPENDENT