By Jessie Taylor
South Africa has the fifth-highest burden of Tuberculosis (TB) globally. But with the Covid-19 pandemic requiring a large-scale healthcare response, the fight against TB has suffered at South African clinics and hospitals.
The disease, considered an epidemic, has a devastating impact on the country and is the leading cause of death. However, with the advances in vaccination development in response to the pandemic, hope has been ignited that TB may soon also see further vaccine development.
Mounting a response against infection
TB is a serious public health issue in South Africa. Almost half a million people develop the disease each year – and more than half of these people are also living with HIV. The disease is the leading cause of death in the country, and around 90 000 people die of the disease annually. South Africa’s over six million HIV patients have a higher risk of contracting TB and a greater chance of dying from the illness.
While there is a correlation between the spread of TB and the large number of people living with HIV in South Africa, the disease is also driven by poor living conditions and late presentation to health facilities. Inadequate nutrition can also reduce the chances of patients recovering. While state facilities provide treatment for TB, the disease can lead to loss of earnings, creating an additional burden for those living in poverty.
Last year, the number of TB deaths worldwide rose for the first time in over a decade, according to a report by the World Health Organisation (WHO). According to WHO, there were 21% fewer people to receive care for TB in 2020 compared to 2019, with a correlation drawn to barriers caused by lockdowns and overstretched healthcare systems. And increased levels of poverty, malnourishment, and lung damage caused by Covid-19 are likely to make more people vulnerable to contracting TB.
Launching a response to the disease comes with a significant price tag. The South African government, PEPFAR, and the Global Fund spend more than USD 1.5 billion annually on HIV and TB prevention, care, and treatment interventions.
There is a further burden created by multi-drug resistant TB, which drains around half of the government’s budget allocated to TB response. Treating one of these cases can reach around R115 000, compared to about R2 500 for a non-resistant case. At the financial burden of treating this disease, it is essential for the government to reduce the number of infections.
A TB-free future
In South Africa, all children receive a vaccine against TB. Only the Bacille Calmette-Guérin (BCG) vaccine has been licensed for use against tuberculosis. The live vaccine stimulates the infant’s immune system to build antibodies to protect against TB. The vaccine is protective against more severe forms of TB. However, the BCG vaccine protection does not last against pulmonary TB in adulthood.
A century has passed since the BCG vaccine was introduced to combat TB more than 100 years ago, with no new vaccines approved for use since.
In 2019, the new M72/AS01E was shown to be 50% efficacious in preventing TB disease in sub-Saharan Africa during a trial. However, these results need to be confirmed by a larger trial.
Pharmaceutical company GSK has licensed the vaccine to the Bill and Melinda Gates Medical Research Institute to drive further development.
Modelling by the London School of Hygiene and Tropical Medicine has suggested that this vaccine could help reduce the number of TB infections in South Africa, resulting in fewer infections and reduced treatment spending by the government.
WHO is joining partners, civil society and affected people and communities worldwide in calling for increased and sustained investments in TB vaccine development.
“Comparing this to the rapid advances made in the development and roll-out of safe and effective vaccines for COVID-19, we can see that political commitment backed by massive investments in research can lead to faster access to life-saving vaccines. Unprecedented public and private financing has supported COVID-19 vaccine research, development and manufacturing scale-up. This clearly shows that we don’t need to wait for over 100 years to access new TB vaccines, but like with COVID-19, increased investments can be a game-changer and alleviate the suffering and deaths caused to millions due to TB – that remains one of the world’s top infectious killers,” says Dr Tereza Kasaeva
Director, WHO Global TB Programme
The rapid development of Covid-19 vaccines has given hope for future development in vaccination against TB. Reducing the number of transmissions is vital to improving healthcare in Southern African nations and reducing TB’s financial and healthcare strain.
What is Tuberculosis?
TB is caused by a bacteria called Mycobacterium tuberculosis. It responds to antibacterial medications (antibiotics), but it requires treatment for at least six months with multiple antibiotics because it is very slow-growing. The disease most commonly affects the lungs but can also cause disease in any other organ of the body, such as the lymph nodes, brain, skin and bone.
TB can occur in people at any age, from newborns to elderly adults. It affects people in all communities. TB is most often spread through coughing, as the droplets of sputum carry the bacteria and may be breathed in by a person nearby. Those with robust immune systems may fight off illness, but those with compromised immune systems (such as those with HIV, diabetes, cancer and other health conditions) may become ill and require TB treatment.
The bacteria that cause TB can develop resistance to the antimicrobial drugs used to cure the disease. Around 1.8% of new cases of TB in South Africa are multi-drug resistant. Multidrug-resistant TB does not respond to the two most powerful anti-TB drugs. This is why it’s essential to complete the full treatment course of any TB medication to prevent Multidrug-resistant TB.