Housing conditions should play a greater role in the global fight against TB, says ARCHIVE’s Peter Williams
Successful campaigns to combat the white plague have been launched, fought and won – only to see re-emergences. The epidemiology of the bacteria is one which the most vulnerable – particularly immuno-compromised individuals and the socio-economically disadvantaged – bear the greatest burden. The treatment strategy involves a short or long course of drug therapy depending on the infectivity of the patient.
Prevention, on the other hand, more broadly involves case detection and diagnosis for treatment, thereby limiting contagion. This is particularly important among the urban poorest, many of whom live in close proximity within environments where proper sanitation is lacking or absent and where pollution often increases their risk to contracting airborne disease. But this link between social conditions and TB transmission/infection is all too often overlooked: a sad truth and a silo effect in the global health and international development arena.
This year, among the poorest countries on our planet, one in every 100 deaths will be attributed to tuberculosis.1 This number is exponentially greater in the Global South considering the disease burden in the South and South East Asia region as well as sub-Saharan Africa. To illustrate how the burden affects developing countries, we can compare countries such as the UK where the incidence rate is 15/100,000 with South Africa where the rate is 407/100,000.2
The highest rates of TB occur in urban settings. Yet as a cause for concern, our world is urbanizing at a rate faster than ever before imagined. More than half of the world’s population now live in cities, and most of the increase in urban population is happening in developing countries.
In fact the world is urbanizing many times faster than the urban-to-rural migratory pattern. Today 1.2 billion people live in slums and the majority of these people live in deplorable conditions where disease, malnutrition and violence are rife. It is therefore no surprise that in 2005, more than 35% of all reported TB cases in Kenya were from the five largest urban areas of the country’s five largest cities – this is undoubtedly linked to what the Kenyan Ministry of Public Health called ‘a phenomenal growth of slums and a slum population’.
In India, there are almost 2 million new TB cases and over 300,000 deaths each year. One study3 by researchers from the National Tuberculosis Institute in Bangalore, India strongly recommended the need for educational interventions specifically aimed at slum dwellers and health providers in Bangalore’s slums. In slum settlements such as Dharavi in Mumbai, the number of health facilities and health workers needed to combat a rising TB epidemic is disproportionately low. According to a report commissioned from Price Waterhouse Coopers4, in India there are three hospitals and 178 beds per 100,000 urban dwellers. Rural populations are much worse off with 0.3 hospitals and nine beds respectively. Clearly the opportunity exists to invest in prevention strategies that integrate the improvement of housing/living conditions as part of the equation.
In Canada, members of the First Nations, Inuit and immigrant populations have shown significantly higher incidence cases of TB when compared to fellow Canadians. What has been well documented is the fact that housing conditions among this community fail to meet the country’s occupancy standard which safeguards against overcrowding in homes – a chief driver of TB transmission at the household level. Documented too is the impact of poor environmental conditions such as poor air quality, inadequate ventilation and overcrowding. Recommendations from a government report suggest that confronting the issue of inadequate housing for at-risk groups in Canada is essential to combating the high burden of TB among such groups.
Researchers including Dr Edward Nardell, Dr Paul Jensen and others have long argued for the importance of environmental conditions in TB infection control. This is based on the evidence showing how its effectiveness can be monitored and assessed in an institutional setting. In fact, the World Health Organization’s own guideline report ‘WHO Policy on TB Infection Control in Health-Care Facilities, Congregate Settings and Households’ sets out an evidence-based policy for the implementation of TB infection control by all stakeholders. The report discusses other institutional settings such as correctional facilities, military barracks, nursing homes, dormitories, refugee camps, and homeless shelters. Although the guideline does make mention of households, it fails to go far enough in discussing how planners, architects and municipal engineers involved in the upgrading of poor urban living conditions could simultaneously prioritize a strategy for TB infection control.
Given all the above, how can we learn from history? Well, over a century ago, TB was the leading cause of death in the United States, particularly associated with the industrializing urban environment. An improvement in living conditions there played a vital role in dramatically reducing the death rate from 195 per 100,000 in the 1900s, to 0.7 per 100,000 in 1985.
Rethinking housing is vital in rethinking the challenge of tackling TB, particularly in an age when our world is urbanizing at a rate much faster than ever before, and when the vast majority of this urbanization is occurring in lower- and middle-income countries. Housing and living conditions ought to play an increased role in an era when preventative and cost-effective strategies are increasingly advocated. Let us seize the chance to think laterally about how to use an age-old strategy to combat a centuries-old problem.
Peter Williams is executive director of ARCHIVE (Architecture for Health In Vulnerable Environments).
1. WHO Factsheet, ‘Top Ten Causes of Deaths’, updated 2008.
2. Public Health Agency of Canada, updated 2010.
3. Suganthi et al, ‘Health seeking and knowledge about tuberculosis among persons with pulmonary symptoms and tuberculosis cases in Bangalore slums’, International Journal of Tuberculosis Lung Disease 12(11):1268–1273
4. Price Waterhouse Coopers, ‘Healthcare in India’ Emerging market report, 2007.