DVT dangers in cars and trains

Travellers are today warned they are at risk from deep-vein thrombosis (DVT) on all forms of transport.

New research suggests passengers travelling in cramped conditions in cars, buses and trains may be in as much danger of developing potentially fatal blood clots as those in aircraft.

Experts now believe the illness can be triggered by sitting immobile during any long journey.

Fears that long-haul flight passengers are not the only ones vulnerable to DVT have already been raised after experts discovered passengers on short flights are also in danger.

Studies at the d'Annunzio Universityin Italy revealed that most blood clots develop in the first two to three hours of a flight.

Professor Belcaro, from the same team, said: "DVT is a travelrelated problem, not a flightrelated problem."

Up to 3,000 British travellers a year develop so-called economyclass syndrome after international flights. The condition is caused by large blood clots in the legs that can form after a long period of immobility.

In only a few cases do clots reach the heart or lungs, where their effects can prove fatal. The most vulnerable passengers are those with weight problems, a history of heart disease or cancer. Women taking the Pill are also thought to be in greater danger.

It was believed low cabin pressure played a major role but Professor Belcaro's team believes DVT is not specifically linked to flying. His team studied people travelling on a variety of long, confined journeys.

A high number of the passengers monitored went on to develop blood clots.

Among the key groups at risk are taxi drivers, many of whom do not take breaks during their shifts.

Workers who spend long periods at desks may also be at risk.