At Brazil's main airports leaflets will be distributed warning passengers of the danger of contracting potentially fatal blood clots on long-haul flights. The threat of suffering deep-vein thrombosis while sitting on the cramped seats of the economy class sections of long distance flights has recently hit the headlines across the world. "The extensiveness of this serious condition can cause deaths and is a costly proposition for the patients and the country,'' says Jackson Caiafa of Brazil's Angiology and Vascular Surgery Association.