Deep vein thrombosis (DVT) is something many long-haul travellers worry about, but it is actually quite rare in otherwise healthy people. The formation of a blood clot (thrombosis) in a deeply embedded vein – most common in the leg – is more likely in those who have had issues with blood clots or a stroke in the past, have cancer or heart disease, are pregnant or a very new mother, are overweight, or have recently had major surgery.

These individuals may benefit from wearing compression stockings, which promote good blood flow, but they must be properly fitted by a pharmacist or GP. Some individuals may also need medication such as warfarin.

Other measures that can help reduce the risk of DVT include wearing loose, comfortable clothes, walking around when possible, drinking plenty of water, steering clear of alcohol and sedatives, and doing calf exercises every half hour. DVT can be symptomless, but signs that should cause concern – and require emergency medical attention – include pain, swelling, aching, tenderness, redness and heat in the calf of one leg, or breathlessness and chest pain if the clot has moved to the lung. This is known as a pulmonary embolism or PE.