The UN helped reverse the AIDS epidemic. It now must do the same for TB.
Anton Pozniak, President of the International AIDS Society, and José Castro, Executive Director of the International Union Against Tuberculosis and Lung Disease (The Union)
In 1996, the momentous announcement of combination antiretroviral therapy (ART) at the International AIDS Conference in Vancouver changed the HIV/AIDS epidemic forever. For the first time, HIV/AIDS could be effectively treated, and it was no longer, scientifically speaking, a death sentence. But four frustrating years later, it was clear to all of us working in the field that the drugs were still only available to those in the privileged West. Something had to be done – and fast.
The 2000 International AIDS Conference in Durban changed all of that. At that historic meeting, the global HIV/AIDS community united around the urgent goal of bringing life-saving treatment to people living with HIV the world over, in particular sub-Saharan Africa, which was (and still is) bearing the brunt of the epidemic.
This commitment was made concrete at the 2001 United Nations High-Level Meeting on HIV/AIDS, which was the first time heads of state from around the world gathered to solve an international health crisis. Heads of state warned of the potential losses of entire generations across countries, and of the threats to security posed by AIDS devastation. Political commitment was sought and obtained and brought about the creation of the Global Fund to Fight AIDS, Tuberculosis and Malaria. Generic pharmaceuticals began producing antiretroviral drugs much more cheaply. Together, the Global Fund and the emergence of generic alternatives were a game changer – drugs started to flow to the world’s most affected region, sub-Saharan Africa, and today, South Africa continues to host the biggest ART programme in the world.
Enormous headway has been made since then, with nearly 22 million people currently on treatment compared to barely one million in 2001. There is still a long way to go. Some 15 million people still need treatment and ART coverage is much lower in some countries and regions than in others, but the progress has been undeniable. Whereas AIDS-related mortality was steadily increasing in 2001, HIV today has ceased to be the biggest infectious disease killer in the world.
As AIDS deaths have fallen, however, tuberculosis—an airborne disease caused by a bacterial infection—has emerged as the world’s leading infectious killer.
There is a tragedy unfolding in the countries most burdened with TB, most of which are low- to middle-income countries. And the most disturbing part of this tragedy is that the world’s deadliest infectious disease is preventable, treatable and curable.
In 2016, an estimated 10.4 million people became ill with TB and 1.7 million lost their lives. Of those 10.4 million, 6.1 million cases are notified, but an astounding 4.3 are “missing”, in that they have not been diagnosed or reported to public health surveillance systems.
More than one million children under the age of 15 fall sick to TB every single year and, of these, 239,000 – nearly one in four – die.
Women and girls are especially affected by TB, which was the 10th leading cause of death among women globally in 2016. Risks are especially pronounced for reproductive-age women. Among pregnant women living with HIV, TB triples the odds of maternal and infant death.
The global response to TB is being hamstrung by a lack of modern tools and technology needed to efficiently prevent, diagnose and treat the disease. Scientific innovation in TB is barely limping along, with diagnosis and management of TB continuing to rely heavily on technologies that are decades old.
In the past 50 years, only two new TB medicines have come to market. What has been needed is a pipeline of a least 18, according to WHO estimates. The slow progress in TB innovation puts us all in danger, as we’re seeing TB drug resistance get worse. TB makes up one in three of all the deaths we’re now seeing from drug-resistant bacteria, viruses and fungi.
We have the same challenges with TB diagnostics. The most widely used tool is more than a century old. An effective test for diagnosing TB in children does not even exist.
It’s a similar story with vaccines. The current one, BCG, has been around for almost a century and has limited efficacy. An effective protective vaccine would help us end TB. In contrast to the US$1 billion currently being spent on efforts to develop an HIV vaccine, only US$100 million is being invested annually in TB vaccine research.
Similarly, there have been global failures to address tuberculosis in the context of the HIV epidemic. HIV infection increases, by up to 30 times, the likelihood that latent TB will progress to advanced disease. Yet even with the biology of these pathogens and the clinical realities of disease interactions clearly arguing for integration, services for HIV and TB are often fragmented, unlinked and uncoordinated.
In some parts of the world, such as South Africa and Eastern Europe, too many HIV-positive people die unnecessarily of TB. Annually, 400,000 people living with HIV die of TB.
Tuberculosis and HIV programme siloes are object lessons in the difficulties of providing better and more streamlined care for patients in dual epidemics. The basic approach to controlling the linked epidemics of HIV and tuberculosis is deceptively straightforward. People with HIV/tuberculosis co-infection who develop active tuberculosis disease need to be found and treated promptly with tuberculosis drugs and ART.
Co-infected individuals at risk of developing tuberculosis must be treated with ART and with isoniazid preventive therapy (IPT). In reality, however, controlling tuberculosis in the context of HIV has proven to be a major health challenge.
Globally, less than half of TB cases are diagnosed before death, and only about half of all patients with tuberculosis know their HIV status. In 2016, only 42% of all people living with HIV who have tuberculosis were estimated to be receiving ART. In 2016, 60% of countries with high HIV/tuberculosis burden did not report the provision of IPT.
There is clearly a case for collaborative HIV and TB programmes. At present, those that exist in countries like South Africa and Tanzania are still the exceptions.
Despite these challenges, the improvements in HIV care and treatment, recognition that both diseases coexist, and a move to more active case finding led to a reduction in annual mortality from tuberculosis in people living with HIV by 37% between 2005 and 2016.
Although undoubtedly beneficial, integration of HIV and tuberculosis services is not always easy to achieve. Infection control, particularly in healthcare settings, is necessary but often difficult under existing conditions, with multidrug-resistant tuberculosis and extensively multidrug-resistant tuberculosis posing lethal risks for people living with HIV.
Something has got to give.
With so many avoidable TB deaths at stake, it is almost surreal to consider that there has never been a UN High-Level Meeting on TB before. The inaugural meeting being held this week in New York has to count: the world’s political leaders have an opportunity to end the unnecessary suffering and loss of millions of lives from TB.
As we did in the case of HIV at the landmark 2001 special UN meeting, we must move from concern to concrete action. We must see tangible commitments and a clear strategy to move forward in order to change the course of history.