The epidemiology of trachoma predicts more blindness in the future

Trachoma is considered the world's leading preventable cause of blindness, with hundreds of millions of people affected and approximately 6 to 9 million blinded as a result of the disease. It was once endemic in much of the world. It disappeared from most of Europe and North America, coincident with the improvements in hygienic conditions that accompanied the expanding industrial revolution in the latter part of the 19th century. Common wisdom states that trachoma is disappearing from much of the world today as a result of improvement in the standard of living. Unfortunately, this is not a realistic perception. In some hyperendemic areas neither the standard of living nor hygienic conditions are improving. Deaths due to acute infections have been reduced and the population is both growing and aging. In some parts of the world, because of demographics, it is likely that there are more people being exposed to trachoma as children and more will survive to old age when trachomatous blindness develops. In these countries there will be larger numbers of blind individuals in the future than there are today. This will tax public health and economic systems in the involved communities.