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Urbanisation Up Close

Jocalyn Clark @jocalynclark discusses the urbanisation of the world’s population and its impact on global health.

Image credit: joiseyshowaa, Flickr
Image credit: joiseyshowaa, Flickr

Undeniably the world is urbanising. By 2050, according to the UN, the world’s urban population will almost double from its 2007 size of 3.3 billion to 6.3 billion people. The developing world will have more urban than rural dwellers by 2030. In terms of health, urbanisation gives rise to new threats and needs when delivering services.

Migration to cities usually means job prospects, educational opportunities, access to health care, and financial security for families. It can bring relief from conflict or land degradation. But it also brings problems associated with inadequate housing, overcrowding, air pollution, and road traffic. Both infectious (pneumonia, tuberculosis) and non-communicable (cardiovascular, diabetes) diseases increase with urbanisation.

I thought I knew big cities – the opportunities and the inconveniences – having lived in Toronto and London and travelled to many more across the developed and developing worlds. Then I moved to Dhaka, one of the world’s fastest growing cities (it grew an astonishing 45% between 2000-2010). Already 14 million people and densely crowded, by 2025 the UN predicts Dhaka will be home to more than 20 million people — larger than Mexico City, Beijing or Shanghai. Without the infrastructure, planning, or governance of those wealthier cities, Dhaka is like a poor cousin of mass urbanisation. Or, as a commentator recently said, it’s the ‘mega city of the poor.’

Mega cities take big city problems and amplify them. There were 10 mega cities (cities with 10 million inhabitants or more) in 1990; there are now 33 – 26 of which are in the developing world. The typical urban issues of climate vulnerability, safety and homelessness can literally engulf mega cities. In turn, the urban poor are disproportionately affected by urbanisation challenges.

Image credit: Ahron de Leeuw, Flickr
Image credit: Ahron de Leeuw, Flickr

This is particularly true of slums, the great, sad reservoirs of urbanisation. In Nairobi, for example, where 60% of the city’s population lives in slums, child mortality in the slums is 2.5 times greater than in other areas of the city, according to WHO. In Kolkata, slum dwellers were found to have higher risk of respiratory infections, meningitis, and asthma than other urban residents.

For climate threats the risk is double-edged. Environmental degradation due to climate change may force a rural Bangladeshi farmer to seek work in the city, but inadequate housing, infrastructure and emergency response means his slum dwelling makes him even more vulnerable in the event of extreme weather like floods or landslides.

Though proximity of health facilities is often touted as a positive aspect of urbanisation, it’s questionable how healthcare alone can address some of these broader challenges. Even where there is evidence of contact with health services – 70% of women in the urban slums of Dhaka use contraceptives, for example – this doesn’t mean even basic public health infrastructure or services are provided. Close proximity to a public or private health facility (or an NGO health worker who visits regularly) fails to overcome the health risks associated with the appalling living conditions of most slums: water sources and latrines are often shared, unhygienic and unserviced. Electricity is patchy at best. The Bangladesh government apparently denies the existence of slums and the fact that 40% of Dhaka residents are now slum dwellers – unsurprisingly, it does not provide public works to these slums.

I recently visited an urban slum, Kamalapur, that serves as a field site for icddr,b. Now comprising an estimated 350,000 inhabitants within a 4 square kilometre area in southeast Dhaka, Kamalapur has no sanitation disposal and a contaminated water supply. The median household income is less than US$60 per month, and people who live there usually have no more than 3 or 4 years of education. As I toured various households with a health worker collecting demographic surveillance data and conducting health screening, the cramped, dusty, dire conditions expected of a poor urban slum were evident. But so was the pride taken in keeping a clean and tidy living space, with family pictures hung on the wall and blankets and clothing folded neatly on shelves. The main street of the slum was bustling with fish and meat sellers, convenience stores, a recycling ‘depot’ and even a hotel. The kids were typically gregarious at spying a visitor and were so playful and inquisitive with me that I forgot to ask why they weren’t in school.

Clearly urbanisation is a major force in the world’s development, and cities including their slum areas are a hotbed of challenges. Advocates stress that building sustainable cities will be a major factor in the success of the post-2015 global health agenda. But in the current goals proposed to replace the MDGs, the vague language feels very far off from the realities of urban slums: “enhance inclusive and sustainable urbanization and capacities for participatory, integrated and sustainable human settlement planning and management in all countries.” Rising to the challenges of urbanisation needs a dedicated, nuanced focus, not forgetting the most vulnerable.



  1. This is a thought provoking article. The issue of health consequences of urban life and how to address require very different thinking as compared to organising services to rural populations, where the focus on accessibility, acceptability and affordability. In urban areas, the challenge is two fold- firstly from the poor external environment (lack of water and sanitation, overcrowding, environmental pollution, noise, poor housing, transport problems etc)and secondly internal( stress of living alone, loss of community, loss of social supports, alienation, lack of relaxation, value framework to guide life etc).
    The mental health impact is one of the most important effects of urbanisation. For example, in India, in most cities, about one in 8 families live in slums (about 15%). The lives of people-men, women, young and old has been graphically presented in a recent book, based on the study of people in a slum of Mumbai, India by Katherine Boo(Behind the Beautiful Forevers, Penguin,2012) . There is struggle for survival, completion among residents rather than cooperation, wide prevalence of conflicts, drug abuse and suicides. It is a frightening picture. Recently, a survey of an another slum in Mumbai reported ‘one in four have identifiable mental disorder’.
    The challenge is two fold. Firstly, we need to understand the living situations of people living in slums and develop practical and feasible measures they can use as part of their day to day life, to address stress and enhance social networks and supports. Secondly, the mental health services have to be not only accessible, acceptable, affordable but also organised in a community based manner, such that they meet the real needs of the people. In this effort there is need for a wide range of ways to share information ( eg. radio, television, mobile phone), increasing change in behaviour through person-to-person communication,( self-help groups) self and community monitoring of health conditions, and most importantly to ‘deprofessionalise’ medical care. There is a bigger need to change the external environment, to make them health promoting rather than illness causative. Besides water supply, sanitation, clean air, there is need for places for relaxation and community interaction( places of worship, parks, playing areas etc). In all these efforts, there is need to think ‘local’ in understanding the needs and meeting them through innovative measures. The goal will have to be ‘rebuild’ healthy individuals and caring communities. Simply transferring what has worked in one place can not meet the needs of others in an another place. There is a challenge which is best addressed before it overtakes all of us living in urban places.

  2. Dear Dr Murthy
    Thanks for your thoughtful comments, and for raising an important area that I neglected to mention in my blog on urbanisation: mental health. I You’ve outlined well the risks and conditions of slums that make residents more vulnerable to mental health issues and you’ve illustrated how neglected the area is in terms of recognition. You’ve also raised another point of importance – the fact that their living conditions preclude opportunities for recreation and relaxation. Utterly lacking in these densely populated and cramped dwellings, and another way that slum living harms health. all the best, Jocalyn Clark

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