New drugs and an effective vaccine are vital to overcome Tuberculosis (TB) but winning the age-old war against the disease will also require a proper understanding of the biology of the bacterium that causes it.
This was one of the viewpoints of Prof Nico Gey van Pittius of the Department of Biomedical Sciences in the Faculty of Medicine and Health Sciences (FMHS) at Stellenbosch University on Tuesday (1 September 2015). He delivered his inaugural lecture in the Education Building on SU's Tygerberg Campus.
Gey van Pittius said Mycobacterium tuberculosis, the organism that causes TB, has had a long and intertwined history with humans and co-evolved with us to become the most successful human pathogen known to date.
"For every defence we have come up with to halt the spread of this organism, it has developed a way to counter and outmanoeuvre our strategies."
Gey van Pittius said M. tuberculosis has a remarkable ability to handle stressful conditions within the body and is also impermeable to a number of compounds.
He added that different strains of the bacterium have acquired different observable (phenotypic) properties through evolution, resulting in strains with, for example, different levels of virulence in certain populations.
"Discovering the biological basis for how mycobacteria became such successful pathogens gives us the opportunity potentially to interfere with this close relationship in a more targeted manner, and hopefully will help us finally to break the bond and eradicate this ancient disease."
Gey van Pittius highlighted the need for new drugs and an effective vaccine against M. tuberculosis to successfully combat TB which remains one of the world's deadliest infectious diseases, having killed over one billion people globally over the last 200 years.
"No vaccine currently exists which effectively protects adults against the most transmissible form of the disease, i.e. pulmonary tuberculosis".
"It is estimated that around a third of the world's population (approximately 2 billion people) is currently infected with M. tuberculosis."
Highlighting the global prevalence of TB, Gey van Pittius said statistics of the World Health Organisation show that in 2013 an estimated 9 million people developed TB and 1.5 million people died from the disease (360 000 of whom were HIV-positive).
He added that the disease is particularly prevalent in the developing world where 90% of all cases occur.
"South Africa has both the highest incidence and prevalence of TB in the world, placing an immense burden on the health of the population."
However, Gey van Pittius did point out that despite this gloomy picture, the worldwide TB death rate dropped by 45% between 1990 and 2013, with around 37 million lives saved between 2000 and 2013 through effective diagnosis and treatment.
Unfortunately, the decline in TB rates is extremely slow, and varies in different parts of the world, he said.
Although antibiotics have helped against M. tuberculosis, the indiscriminate use of these drugs made the bacterium more resistant, Gey van Pittius argued. Bacterial resistance is cause for extreme alarm, he said.
He added that although we may have won a few battles against the bacterium, the war is far from over.
- Photo: Proff Marietjie de Villiers, Deputy Dean: Education at the FMHS, Arnold Schoonwinkel, Vice-Rector: Learning and Teaching, Nico Gey van Pittius, Jimmy Volmink, Dean of the FMHS, and Paul Van Helden, Head of the Department of Biomedical Sciences at the FMHS.
- Photographer: Hermien Nel
