Risks to health in informal settlements

IIED researchers have long highlighted the health risks faced by people living and working in informal settlements, which are exacerbated by vulnerability to climate change and now also COVID-19.

Article, 09 June 2022
Urban health equity
Multifaceted partnerships to promote the social, environmental and political determinants of urban health
A woman sits in the courtyard of a building, washing clothes in a small bowl.

A women washes clothes in a small bowl in Karakata informal settlement, Dar es Salaam (Photo: Slum Dwellers International via Flickr, CC BY 2.0)

Informal settlements (‘slums’) are widespread in cities across many low-income and middle-income countries and are now home to more than one billion people. These areas lack formal government recognition, and residents typically face multiple socioeconomic, environmental and political exclusions that all contribute to ill health. 

Residents typically lack secure land tenure and often live in overcrowded, substandard dwellings located on marginal lands or unsafe sites. 

Elevated levels of environment-related risks are among the major causes of serious illness, injury and premature death in informal settlements. People living and working there face a large spectrum of health risks, from ‘everyday’ risks such as infectious and parasitic diseases to small- and larger-scale disasters. 

While some upgrading initiatives have successfully fostered health and wellbeing, most informal settlements still lack vital risk-reducing infrastructure and services, such as clean piped water, sanitation and drainage, solid waste collection, healthcare and emergency services. 

Large inequalities

Reflecting their inadequate shelter and service provision, residents of informal settlements often experience markedly worse health outcomes than their fellow city residents. 

Children are especially vulnerable, as the combination of malnutrition and recurrent diarrhoea leads to stunted growth and longer-term effects on cognitive development. Women with precarious informal livelihoods, limited access to infrastructure, and gendered care burdens also face acute risks to their health and wellbeing. 

Beginning at birth, these urban health inequalities are often reproduced over a lifetime and may be exacerbated by vulnerability to climate change – which increases loss of life and injury from extreme events – and now also COVID-19. 

What IIED has done

Health is affected by several factors arising from the physical and built environment, alongside an array of political, social and economic determinants of health. 

To understand and promote these determinants of health with a focus on informal settlements, we have published and contributed to academic and policy research including in The Lancet, the Journal of Urban Health, and Environment and Urbanization

We have repeatedly highlighted the need for better data collection on these complex health risks in informal settlements. Our review of literature on health in the informal settlements notes that, with greater attention to the multi-faceted needs of low-income communities, governments can create interventions to ensure that urban centres fulfil their enormous potential for health. 

To help improve health in informal settlements, we also argue that ‘slum health’ should be promoted as a separate topic of enquiry for health policymakers and urban decisionmakers.

We have argued that the people who are most affected must have a more influential role in setting priorities and making decisions, helping to ensure that limited resources are well targeted and can address longstanding inequalities.

What IIED is doing

We continue working with partners to generate strategies that address multiple risks and increase recognition for community-led processes. 

This includes highlighting the pivotal importance of informal settlement upgrading and its potential to foster health and wellbeing and help communities manage COVID-19.

Additional resources

Revealing and responding to multiple health risks in informal settlements in sub-Saharan African cities, David Satterthwaite, Alice Sverdlik, Donald Brown (2018), Journal of Urban Health 96: 112–122.  

The history, geography, and sociology of slums and the health problems of people who live in slums, Alex Ezeh, Oyinlola Oyebode, David Satterthwaite, Yen-Fu Chen, Robert Ndugwa, Jo Sartori, Blessing Mberu, G J Melendez-Torres, Tilahun N Haregu, Samuel I Watson, Waleska Caiaff, Anthony Capon, Richard Lilford (2016), The Lancet

Improving the health and welfare of people who live in slums, Richard Lilford, Oyinlola Oyebode, David Satterthwaite, G J Melendez-Torres, Yen-Fu Chen, Blessing Mberu, Samuel I Watson, Jo Sartori, Robert Ndugwa, Waleska Caiaff, Tilahun N Haregu, Anthony Capon, Ruhi Saith, Alex Ezeh (2016), The Lancet

Ill-health and poverty: a literature review on health in informal settlements, Alice Sverdlik (2011), Review article, Environment and Urbanization


Anna Walnycki (anna.walnycki@iied.org), senior researcher, IIED's Human Settlements research group