While the number of cases of tuberculosis has plunged in Britain, the development of highly drug-resistant strains mean this disease may be poised to make a comeback, says Jane Downey.
Prior to the discovery of streptomycin in 1952 by scientist Selman Waksman, tuberculosis (TB) was a major killer, not only in the developing world, but also in the UK. Although some regained their health spontaneously without effective medication, many did not - including the novelist George Orwell who, according to his biographer, battled feverishly to complete his seminal work 1984 before the disease laid his creative genius to rest in 1950.
TB is caused by bacteria belonging to the mycobacterium tuberculosis complex. From a global perspective, in 2011 there were nearly nine million new cases of TB and 1.4 million deaths from TB, and it is the leading cause of death among curable infectious diseases (Health Protection Agency (HPA), 2012).
Tuberculosis is the leading cause of death among curable infectious diseases."
In 1991, the World Health Organisation (WHO), concerned by the steadily increasing number of cases of TB globally, implemented a strategy with two major targets. The first was to detect 75% of new sputum-positive cases of TB and the second was to cure 85% of these cases by the year 2000.
In 1994, this strategy was enhanced by focusing on a number of key components such as government commitment, case detection and standardised short-course chemotherapy for all confirmed sputum smear-positive cases, with a system of regular medication supply together with a programme monitoring system.
This strategy became known as "DOTS" (directly observed therapy) and has subsequently been expanded and implemented in 182 countries. DOTS implementation has assisted countries in improving national TB control programmes and managing the disease effectively. By 2004, more than 20 million patients had been treated by DOTS programmes globally and more than 16 million of these had been cured. Mortality due to TB has been falling and TB incidence declining or stabilising in all world regions except sub-Saharan Africa and Eastern Europe (WHO, 2010).
In the UK, TB was a major concern for the