Tuberculosis (TB) has always suffered from being easily forgotten. We’ve had a generalised epidemic since the 1900s – for more than a century – and we have not really made headway, says the University of Cape Town’s (UCT) Professor Linda-Gail Bekker, a physician-scientist with a keen interest in HIV and TB. Weighing in on the seriousness of the TB epidemic is Professor Thomas Scriba, who directs the clinical immunology laboratory at the South African Tuberculosis Vaccine Initiative (SATVI) at UCT.
It’s a disease that claims the lives of around 1.5 million people each year and estimates last year suggested that 2 billion people were infected worldwide. It’s present in all countries and age groups globally. It is also a disease that is curable and preventable, but that has been grossly neglected for years and especially sidelined for the past two years, where Covid-19 has taken the centre stage.
“Tuberculosis (TB) has always suffered from being easily forgotten. We’ve had a generalised epidemic since the 1900s - for more than a century - and we have not really made headway,” Professor Linda-Gail Bekker, a physician-scientist with a keen interest in HIV and TB, told Health24.
Bekker is also the co-principal investigator on SA’s Sisonke Covid-19 vaccine trial.
“I would say not only have we taken our focus off TB in the last two years, but I would argue that we haven’t really had sufficient focus on the problem prior to Covid.”
Her comments underscore this year’s theme for World TB Day - ‘Invest to End TB. Save Lives’.
“And there’s no question that, when you see what was invested in Covid - the research that went into preventive and therapeutic options - if we have even just some of that for TB, it could be terrific,” she added.
According to the World Health Organisation (WHO), the aim of this year’s theme is to bring attention to the urgent need to invest resources for the fight against ending TB, which, it says, is especially critical in the context of the current Covid pandemic that has dampened the progress made to end TB.
Last year, a report by Stop TB Partnership, for example, noted that 12 months of Covid eliminated 12 years of progress in the global fight against TB.
'Single largest infectious killer for centuries'
Also weighing in on the seriousness of the TB epidemic was Professor Thomas Scriba, who directs the clinical immunology laboratory at the South African Tuberculosis Vaccine Initiative (SATVI), University of Cape Town.
“TB is and has been the single largest infectious killer of humans for centuries … As a result [of disruptions caused by the pandemic] thousands of additional people have died from TB and for the first time in 15 years, the number of deaths from TB has increased year on year in 2021.”
Importantly, Scriba explained that even if a patient with TB is successfully treated, they are likely to have long-lasting and debilitating health problems, especially with respiratory impairment.
“TB doesn’t just sit there in your lungs. If you have the disease, it’s progressive, and many of the chronic lung disorders we see in this country are in people who’ve had previous TB. And once you’ve had previous TB, even if you’ve been treated, you have a high risk of getting it again.”
There should be more awareness
South Africa is one of the 30 high TB burden countries which accounts for the majority of new cases. And in a country like ours, with a generalised TB epidemic, everybody needs to be aware of the disease, know what their risk is, and what they could be doing to reduce their risk, said Bekker.
“It’s a little bit like what we learned with Covid - the two are very similar. They’re airborne diseases that can be reduced by having better ventilation, awareness of our close contacts, and making sure infectious individuals do not infect other people.
“Yet, somehow we haven’t had that same concerted effort. And instead of utilising the opportunity of saying ‘same-same’ during Covid, we put all our energy into Covid and completely forgot TB which is a shame,” she added.
Knowing your risk
Unfortunately, people generally have a nonchalant attitude toward TB, even though it kills far more commonly than Covid does, said Bekker, adding: "And so we need to take a whole new view on the TB epidemic."
Scriba said that children below the age of five are particularly at risk for TB. Adults living with HIV, diabetes, smokers, people who abuse alcohol, and those who are undernourished are also at high risk. “This represents a very large proportion of the South African population,” he said.
Bekker also commented: “By the time a child enters primary school, one in five will be infected with TB. By the time they are mid-way through high school, one in two is infected - that’s actually far from normal and doesn’t happen anywhere else in the world.”
Adopting active-case finding approach
Several researchers have pointed out that SA’s healthcare system needs a better approach to adopting active case-finding, which refers to locating and diagnosing TB, either in people who may not recognise that they have symptoms of the disease, or those who do but do not, or cannot, access healthcare facilities.
Bekker agreed, saying that the key to TB is to find a case before that case is able to transmit the pathogen to others.
“It's not just about curing and treating someone when they’ve had the disease for a really long time. You want to get to them as soon as possible so that they don’t have an opportunity to transmit to others. That needs very active work - to try and reduce the time between acquiring and developing infectious TB and passing it onto others,” which is partly due to diagnostics, she said.
Similarly, Scriba believed that resources for finding and diagnosing people with TB, and providing them with antibiotic treatment, have been inadequate for decades. “It is imperative that much more is done to improve care of those with TB and programmes to find, diagnose and treat people with TB,” he said.
SA’s neglected vaccine trial
Around four years ago, SA ran a trial of a candidate TB vaccine that showed a 50% reduction in the progression from infection to disease. A follow-up trial has not been done, which means that the data cannot be confirmed. “It’s not months, but years later, and we have not pursued that. It’s mind blowing,” said Bekker, who drew attention to the few months it took to develop several Covid vaccine candidates.
The pandemic has shown what can be done when there is real resolve to reduce the impact of a communicable disease, said Bekker.
Reporting by Health-E News last month noted that there are currently nine candidates in phases 2 and 3 of the TB vaccine clinical trials. But Mark Hatherill, a researcher from SATVI, told the publication that if none of the candidates are successful, there were very few that could fill those positions in the next five to ten years.
Investment, investment, investment
For Scriba, urgency and real commitment to tackling the TB epidemic is needed.
“The unprecedented response to the Covid-19 pandemic shows that it is possible to mount a massive, rapid and comprehensive response to an infectious disease killer of this magnitude. It is critical that significantly more investment is devoted into research to improve strategies to find, diagnose and treat people with TB,” he said.
This would include tools and strategies used to find and treat people earlier, before they develop irreversible lung damage and transmit the bacterium to others. “There has been exciting and promising progress in recent years, but the chronic underinvestment makes this progress slow and frustrating,” added Scriba.
Additionally, attention also needs to be paid to investing in strategies to prevent TB. Said Scriba:
“For a disease that is so difficult to diagnose and treat, vaccination to prevent development of TB is a no-brainer. But, we have one TB vaccine, which is 101 years old! Yet, we have learnt that it is possible to identify a new infectious organism and develop and deploy several new vaccines within two years if there is enough incentive, investment and cooperation.”
Around 150 vaccines for Covid are in clinical trials globally. Sadly, this figure for TB vaccines is ten times lower. The response to TB should be no different to the response to that of Covid, said Scriba.