Is improving housing in sub-Saharan Africa equal to improving health?
By Donal Bisanzio, Global Health Epidemiologist, RTI International
Housing has always been one of the central pillars of human security and wellbeing. As such, Sustainable Development Goal 11 aims for universal access to adequate, safe, and affordable housing by 2030.
In high-income countries, most of the population already has access to adequate housing. However, in low- and middle-income countries in sub-Saharan Africa and elsewhere, people still live in houses made with non-durable materials like earth, mud, and straw, and which lack conventional features like windows, restrooms, and a proper cooking stove.
Thus, countries in sub-Saharan Africa have experienced explosive population growth in recent decades, with the population of the region expected to reach 2.5 billion by 2050. Demand for housing will increase exponentially during the next 30 years and ensuring adequate access to quality housing will be a challenge for many countries. Meeting that challenge could result in significant gains for global health.
During the past 15 years, the percentage of housing with access to safe water sources, a proper latrine, enough living space, and made with durable construction materials has doubled in sub-Saharan Africa. I am a co-author of new research published in Nature examining this dramatic transformation.* The study finds that the percentage of houses in sub-Saharan Africa which meet the definition of “improved” has more than doubled, rising from 11 percent in 2000 to 23 percent in 2015. While 53 million sub-Saharan Africans lives in slums (half of the urban population) and 595 million rural inhabitants do not have access to improved housing (four-fifths of the rural population), 134 million people have benefited.
This trend has important implications for health. In sub-Saharan Africa, improved housing has been linked to reduced exposure to mosquitoes and a considerable corresponding reduction of mosquito-borne diseases, specifically malaria. Structural features of improved housing, like walls made using cement or bricks, roofs made with non-natural materials (metal or tiles) with closed eaves, and proper doors and windows all create barriers to mosquito access. Additionally, interventions targeting mosquitoes such as indoor residual spraying of households with insecticide (IRS) and use of insecticide-treated bednets perform better when applied in improved dwellings. Insecticides used for IRS last longer on brick and cement walls compared to mud walls, and hanging bednets — which increase protection against mosquitoes at night — is less troublesome in improved structures.
Improved housing also decreases exposure to other pathogens. For instance, two criteria of improved housing — as defined in our study — are sanitation and access to safe water sources, both of which are essential for reducing the prevalence of pathogens that cause diarrhea, another leading cause of child mortality in low- and middle-income countries besides malaria. Home access to water also reduces exposure to schistosomiasis, a widespread water-borne neglected tropical disease in sub-Saharan Africa. Additionally, a house floor made with concrete or other non-earth materials reduces exposure to soil-transmitted helminths.
The wave of housing improvement happening across sub-Saharan Africa has thus far been driven by an increase in economic growth in the region, which has provided greater financial means for people to invest in making their homes more comfortable and durable. Government and private-sector investment in programs that facilitate improved housing would amplify this trend — and its positive effects on health. Improving housing as a health intervention — implemented in addition to and complementing other health interventions — could rapidly reduce the burden of several infectious diseases and help their citizens lead healthier, more productive lives.
*Lucy Tusting et al. (2019) Mapping changes in housing in sub-Saharan Africa from 2000 to 2015 Nature 568: 391–394; https://www.nature.com/articles/s41586-019-1050-5).