The city, its people, their health and tuberculosis.

Editorials The city, its people, their health and tuberculosis City life appears destined to dominate the future of mankind in both the developed and developing world. If current trends persist into the coming decades, all population growth at global level will occur in towns and cities [1]. The number and size of big cities are set to increase. The proportion of the world's population living in cities is forecasted to go up from 52% in 2011 to 67% in 2050 [2]. In more developed regions, including much of the European Union (EU), close to 90% of the population is expected to become urbanised by 2050. Economic pressures of different forms fuel these trends. For many people, however, the benefits of resettlement in cities and towns come at a price of greater risk to security and health through social exclusion. The rapid urbanisation that followed the Industrial Revolution led to a deterioration in public health in a number of western European cities. Homelessness, poverty, migration , overcrowding, and substance abuse are common in cities today and these risks often overlap in the same individuals, contributing to their descent into ill health. Tuberculosis (TB) tends to be barometric of this trend. It has been known for a number of years that the risk of TB in many western European countries was higher for persons dwelling in a big city than those in rural areas; this was documented in a study of 20 cities in 11 European countries in 2003 [3]. However, the paper by De Vries et al. in this issue of Eurosurveillance presents a more recent roundup of European data from more cities and more countries [4]. It also reflects the realities of a more diverse EU, which has expanded eastwards since 2004 to encompass countries which generally had higher rates of TB than most of the EU15 countries before the enlargement. The data from this study thus allowed the authors to comment on observations which are better profiled than before. One of these is the inverse relationship between overall TB national case rates and the ratio of TB case rates in cities and towns compared with the rest of the country. This finding lends evidence to the widely held belief that as TB becomes rarer, the epidemic becomes more concentrated in place and population. It is also noteworthy that most cities with a rate ratio larger than 2.0 had a …