I was flying home from Johannesburg to Cape Town after attending the TB Think Tank meeting in May 2023. I said a perfunctory “hello” to the young woman dressed in hiking gear and boots in the seat next to me. It had been a long day, and I was tired, but even when I am feeling more perky, I generally don’t get into conversations on aeroplanes.

I took out my book. My fellow traveller was also reading, on a Kindle. Half an hour before landing I finished my book, and as I closed it with a contented sigh, she asked politely “excuse me, what is the book you are reading?” I showed her the cover of The Bomber Mafia by Malcolm Gladwell and said that it was an excellent book.

She listened with interest as I told her that I had been surprised by how much I had enjoyed a book about aerial warfare and American Air Force bomber pilots — not a topic that would normally interest me. It is a sign of a good writer when one’s interest is unpredictably piqued. (The topic of the book became even more interesting to me after watching the movie Oppenheimer). She took out a notebook and wrote the author and title down.

We continued to chat and I learned that she was a post-grad geology student at Stellenbosch University on her way home after a field trip to Kruger Park and Eswatini. We discussed why South Africa is so geologically fascinating and what geologists have discovered about the very ancient history of the earth from this country. She asked what I had been doing in Gauteng, and I told her that I had been attending a meeting about tuberculosis (TB), which set off a conversation about TB.

She was surprised to learn that it is the commonest cause of death in South Africa, and that more people died of TB (50-60,000 annually) between 2020 – 2022 than the annual average of around 35,000 official Covid-related deaths during those three years.

As the plane was circling to land, she said that she had really enjoyed our conversation and then added “I don’t know anyone who has had TB”.

I was not really surprised. It was a variation of many similar conversations I have had over many years. For doctors like me who have worked predominantly in the South African public sector, TB is a basic staple, a familiar constant in our regular clinical work. And yet many of my tertiary-educated, middle-class fellow South Africans, if asked what they know about TB, will say something like this young geologist-in-the-making. Most people in this country know more about Covid than TB.

There are in fact quite a few similarities between Covid and TB. Both are spread by breathing, coughing or sneezing tiny airborne infective “droplets”. Both are respiratory infections and affect the lungs but also other parts of the body. Both have a range of clinical manifestations, from asymptomatic to fatal and the response of individuals to both is affected by their immune systems and probably genetic factors.

A major difference between Covid and TB has been the response of governments, the medical community, the WHO and society in general. I wrote about the similarities and differences between TB, HIV and Covid in a Maverick Citizen article in June 2020.

I told the student geologist that there was a good chance that someone she knew had had TB, but might not have told her, as there is still a lot of stigma related to TB, for complex reasons. And now that she had met me, she knew at least one person who had had TB — I was treated for TB as a five-year-old, so I have a long relationship with TB. It started up close and personal, then I learnt about TB at medical school and as a doctor working in the public sector, I have treated many TB patients.

South Africans need to know more about TB. South Africa is among the World Health Organisation’s list of 30 high-burden tuberculosis countries and has one of the highest rates of notified TB in the world. A recent national survey confirmed that tuberculosis remains rampant, with an estimated prevalence of 852 cases per 100,000 population.

For comparison, Brazil (which South Africa is often compared to), has a prevalence of 37 cases per 100,000. People living with HIV in South Africa continue to have one of the highest burdens of tuberculosis globally, with an estimated prevalence of 1,734 cases per 100,000 population — almost double that in HIV-negative individuals, despite the massive scale-up of HIV diagnosis and treatment. Given how serious the problem of TB is, we need a “whole of society” approach to tackling TB. We need better public health messaging (radio, TV, and print media) about TB, more teaching about TB in schools and tertiary education institutions, as well as in workplaces.

What should South Africans know about TB in 2023?  

There have been a lot of new and positive developments in TB care and treatment in the last decade. This is a good news story. Let me summarise what I think all of us should know about TB in the form of some “case notes”, the way in which doctors and nurses have traditionally written up notes about patients or medical conditions.

Aetiology (cause)

TB is caused by a bacteria called Mycobacterium Tuberculosis, first identified by Robert Koch in 1882.

History — how long has TB been around?

TB is one of the oldest known diseases. It is believed to have originated with the first domestication of cattle. It was called “phthisis” in ancient Greece, “tabes” in ancient Rome, and “schachepheth” in ancient Hebrew. In the 1700s, TB was called “the white plague” in Europe due to the paleness of the patients. Johann Schonlein, a German professor of medicine, coined the term “tuberculosis” in 1834, from the Latin word tuberculum, meaning a “small swelling”, but even after this, it was commonly called “consumption” in the 1800s.

Public Health impact/epidemiology — what is the big picture?

TB is the most serious global infectious disease — it occurs in every country and is the leading infectious cause of death worldwide. Every year at least 10 million people become ill with TB, and despite it being a preventable and treatable disease, 1.5 million people die from TB every year, which equates to around 4,300 every day.

Clinical manifestations/symptoms: How does TB make a person sick?

TB causes disease at all ages — from newborns to the elderly. It affects the lungs predominantly. This type of TB is called pulmonary TB, or PTB. Typical symptoms of PTB include cough, weight loss, low-grade fever, sweating, and loss of energy. Recent research shows that many people who have TB have no symptoms, which is a new challenge to address. TB can also infect other parts of the body such as a person’s joints, spine, brain, abdomen and skin — this is called extrapulmonary TB (EPTB). The symptoms of EPTB would depend on the site of infection.

Diagnosis/Investigations: How do we know for sure that a person has TB?

The standard first-line test is a sputum sample sent to the laboratory for a GeneXpert test. This is a new and very accurate test, and the result should be ready in 24 hours or less. The GeneXpert test will also show if the person has drug-sensitive TB or the more serious drug-resistant TB, which means that the TB bacteria do not respond to the standard TB drugs, and the person needs more potent medication.

There are other investigations like X-rays, ultrasound, biopsies, lumbar punctures, and CT scans which can also help diagnose TB. A person can get tested for TB for free at any primary care clinic. Testing in the private sector is expensive.

Management: What to do about TB?

TB is both treatable and preventable, which makes the high mortality rate particularly iniquitous.

Let’s start with treatment. There has been effective medication for TB available since the early 1950s. TB treatment in South Africa currently consists of four antibiotic drugs combined into one fixed-dose combination tablet. The duration of treatment for TB has decreased from 18 months in the 1950s, to nine months in the 1970s, to six months since the 1980s and now (drum roll!), we are on the brink of a four-month regimen, containing some newer drugs. This is seriously significant progress.

Drug-resistant TB treatment has also benefited from intensive research in the last two decades. The discovery of a cluster of extensively drug-resistant (XDR) TB patients in Tugela Ferry in KZN in May 2005 was to be a seismic event in the history of drug-resistant TB in South Africa, as well as the rest of the world.

Unfortunately, 52 of the 53 patients died, a terrible and dramatic outcome, but one that had the effect of galvanising global attention and action. The treatment options for people with drug-resistant TB, and particularly XDR-TB at the time were dire and horrible.

In 2010, a person being treated for drug-resistant TB typically endured 240 painful injections and swallowed up to 14,600 pills, and after all that, the chance of being cured was about 50%. There has been enormous progress since then.

Most people with drug-resistant TB can now be successfully cured in six months (instead of 18–24 months) with much more tolerable oral medications (pills). Daily painful injections of drugs with very serious side effects are thankfully no longer the standard of care, as they were up until 2019. Only people previously treated for drug-resistant TB, their families and their care providers can truly grasp how life-changing and life-saving these developments have been.

It is important to know that once a person starts taking TB medication they become non-infectious within two weeks, and they will not transmit TB to close contacts. After completing TB treatment, a person is said to be cured, and is no longer infected with TB.

Unfortunately, some people develop damaged lungs as a result of severe TB disease, which will affect them lifelong. A person does not become immune to TB, and can become ill with TB multiple times, and if they continue to be exposed to TB in their environment, can get a second or third episode of active TB disease.

Prevention is always better than cure

There are non-pharmacological prevention options like wearing masks in crowded places such as taxis and clinics, as well as opening windows and ensuring adequate ventilation. There are also medication options for prevention. These are based on the fact that many people have so-called “latent” TB, which means a person is infected with TB, but it does not make them sick.

However, the chance of TB infection progressing to TB disease, which also makes a person more likely to infect others, is unpredictable. So, the most recent South African guidelines, which were released on World TB Day (24 March 2023) have extended the eligibility for TB Prevention Treatment (TPT) to include all close contacts, which includes household members and work contacts, of people with TB.

Previously TPT was only routinely offered to children under five, people living with HIV and others with immune-compromising health conditions. There are various options for TPT, which range from taking one type of TB medication daily for six months to taking two medicines weekly for three months, making a total of 12 doses in all. The details of how to implement this radical new policy are still being worked out by the provincial health departments.

Prognosis: The likely course of a medical condition — what’s the future?

So, what can we expect regarding TB in the future? The good news is that there is a lot more research attention being focused on TB, at all levels. Research covers the spectrum from a basic science perspective, in which researchers are trying to better understand the TB bacteria, as well as its relationship with the human immune system, to the development of better diagnostic tests, treatment options and optimising delivery of TB care in health programmes.

The holy grail in TB research remains the development of a better TB vaccine. The Bacille Calmette-Guerin (BCG) vaccine is currently the only available TB vaccine. It was developed in 1921, and while it has been widely used for more than 100 years, its efficacy remains controversial, and there is no universal international BCG vaccination policy.

BCG vaccination in infants was made mandatory in South Africa in 1973 and is given as an injection to newborns. A recent study in Lancet Global Health reported that infant BCG vaccination was only 37% effective against TB in children under five years and that it did not offer protection to adolescents or adults.

South Africa does not recommend re-vaccination after birth, because the protective value wanes. So, it’s better than nothing for children under five, but not great. There are many TB vaccine trials underway, and while some are quite promising, for many and complex reasons we are unlikely to have a more effective TB vaccine than the vintage BCG in the very near future. The developers of an effective TB vaccine, like those pursuing a potent HIV vaccine, will deserve multiple Nobel prizes.

The most important factor that would improve the TB situation in South Africa would be the socioeconomic improvement of the majority of the citizens. While anyone can get TB (and healthcare workers who are exposed all the time are especially vulnerable), poverty is a powerful determinant of the risk of getting TB. The crowded and poorly ventilated living and working environments associated with poverty constitute direct risk factors for TB transmission, and poor nutrition compromises the immune system which protects people from TB.

So, we have a way to go before TB in South Africa becomes one of those rare diseases treated by infectious disease experts at specialist clinics in referral hospitals, as is the case in the Global North, rather than being a very common condition seen by nurses and doctors working at every level of the public healthcare systems in the Global South.

Until South Africa is a more equitable society where we can all participate and prosper and until we have an effective TB vaccine, we need to intentionally support anyone who we know who has TB.

We need to value and support our health workers who provide care to people with TB. We need to challenge TB stigma by being well informed about TB, spread awareness and keep informed about this critical health condition that likely infects or affects someone each of us knows.

I am grateful to the geology student who inspired me to write this article. I hope that she reads it, and her friends and fellow students, as well as many other South Africans.  It can be fun and interesting to strike up spontaneous conversations with strangers, like in the long queues at Home Affairs or the traffic department.

Armed with what you learned from reading this article, try asking some questions about TB as conversation starters with your friends and family, or next time you are bored and feel like chatting to a stranger. You never know how the conversation might develop. You might find yourself becoming a TB advocate. DM

Janet Giddy is a Family Physician who has worked in public health for the Department of Health, and NGOs such as Keth’impilo and Medicines Sans Frontières. She currently works for TB Proof, an NGO which was set up by healthcare workers who had been diagnosed with tuberculosis. TB Proof is a TB advocacy organisation that has a variety of programmes, including working with community leaders to improve community awareness of TB.