[Urbanisation, health and travel]

2007 can be considered as a milestone in human history: over 50% of the world population lives in cities. In 2030, 60% of the population will live in cities. Currently the urbanization process prevails in developing countries, particularly in Asia and Africa. Cities in developing countries are characterised by an important heterogeneity, where the poorest areas are next to the richest. Urbanization has an important impact on health and diseases profile. An increasing number of travellers visit cities in tropical areas. Risk factors such as air pollution, heat, security, accidents or infectious diseases prevalent in urban environment should be taken into consideration when advising travellers.