A vaccine for Covid-19 may have prevented this tragedy and many others like it. But so too could have a TB vaccine.
The extraordinary pace of the development of numerous vaccines to protect people from Covid-19, and the urgency of the current rollout across the globe continues to receive unprecedented attention. And rightly so. We need to vaccinate as far and wide as possible to get ahead of variants, transition out of the pandemic and eventually relegate this novel coronavirus to a status something akin to a common cold. In this regard the decision of President Joe Biden’s administration to facilitate the transfer of raw materials for vaccine production to India, where case numbers are soaring, is significant: broader manufacturing of low-cost vaccines is going to get us to the endgame sooner.
But why not go the extra mile and try to stamp out all infectious diseases? As of late, there has been promising progress made on developing vaccines for other infectious diseases, like malaria. But we need to go further. The mistakes made around the world in responding to Covid-19 are staring us in the face. And so too are some of the solutions. During this World Immunization Week, we should pause to consider what we’ve learned and how we can use it to address the issue of other deadly infectious diseases that devastate parts of the world.
For example, this global vaccination effort will lead to the licensure of Covid-19 vaccines based on established vaccine technologies, validation of novel vaccine platforms, accelerated regulatory pathways and systems for anticipated vaccine implementation. The public and private partnerships that drove Covid-19 vaccine development and the set-up of programs like COVAX (the vaccines arm of the Access to COVID-19 Tools (ACT) Accelerator launched by the World Health Organization and partners early in 2020) to distribute vaccines equitably to lower and middle-income countries, might also provide a model for other diseases that have a foothold in the developing world.
We’ve actually been here before.
During the 2014-2016 Ebola outbreak, a vaccine candidate was developed, manufactured, tested and demonstrated to be highly efficacious in preventing infection with Ebola, and was licensed in record time.
Some of us involved with the Ebola vaccine speculated then that vaccines for defeating other infectious diseases like HIV and TB vaccines could be envisioned through lessons learned from the successful liaison between innovative science and dynamic private-public partnerships that we saw come together during that crisis. We also said that defeating HIV and TB would ultimately depend on vaccines being affordable and accessible across the globe, particularly in the places where the burden of these diseases remains — the developing world.
The world didn’t take heed back then, but today we have a second chance to get things right.
Until the pandemic hit in 2020, TB was the world´s leading cause of death from an infectious disease. It likely will be so again post-Covid -19. Despite a vaccine and drugs to prevent, treat and cure the disease, TB affects 10 million and kills approximately 1.5 million people each year; it is a disease of poverty. One in four people living with TB reside in India — eliminating TB globally starts there.
Diagnosing TB still relies on very basic tools compared with other diseases. We’ve only had a handful of new drugs to cure TB in the past 50 years, so treatment can still take months and, unsurprisingly, adherence can be poor. In much the same way that stopping short of finishing a full antibiotic treatment can cause an illness to rebound, TB treatment interruption can also lead to multidrug-resistance that renders drugs ineffective.
Covid-19 threatens to reverse progress in the global TB response by up to 12 years, and result in an estimated 1.4 million additional TB deaths due to lack of access to TB services during lockdown and recovery through 2025, according to the Stop TB Partnership. The one TB vaccine we do have — Bacillus Calmette-Guérin (BCG) — is now 100 years old. BCG doesn’t prevent the most common form of respiratory TB in adults and is not completely effective against the most severe forms of TB, such as TB meningitis, in children. That’s why we need better TB vaccines now, more than ever, if we are seriously committed to eliminating the disease.
New TB vaccines are in the pipeline. Two candidates, MTBVAC and VPM1002, are entering late-stage clinical trials. A third candidate, M72, was shown to be 50% effective in preventing TB disease in people already infected with latent TB in a Phase IIb trial in 2019. It is licensed to the Bill and Melinda Gates Medical Research Institute, and will now enter a final phase of testing.
But compared to Covid-19 or Ebola, progress on TB is slow and underfunded: TB research and development faces an annual $1.1 billion shortfall. Considering Operation Warp Speed’s $18 billion budget for Covid-19 vaccine development, it is almost inconceivable that TB vaccine research only attracted $117 million globally in 2019.
As we’ve seen over the past 12 months though, things can change quickly. Never before has the debate around the moral imperative to vaccinate everyone, everywhere, dominated conversation on a global level. But, just as importantly, the discussion around vaccine equity is also bringing to our collective consciousness the scientific reasoning behind the need to vaccinate the world: no one is safe from the virus until everyone is safe.
Over a year into the pandemic, most people have been touched by Covid-19 in some way and subsequently have a much more acute sense of just how interconnected we really all are. We’ve all seen first-hand how contact with one infected person can affect their immediate circle; how the virus can shift from one neighborhood to others — across the country and overseas. We can understand that someone infected miles or oceans away can ultimately affect us. That´s a newly lived reality for many, particularly in the West.
We have an opportunity to seize the moment, to convince political leaders to invest in “faraway” diseases. Covid-19 has demonstrated that where there´s political will, there´s funding.
One would think that public support for such measures might now be at an all-time high and we ought to build on and leverage the sense of relief and safety people feel from being vaccinated over the next year. But the window of that political will close quickly. Once we emerge from the grips of Covid-19 and people begin to resume some sense of pre-Covid normality, it will be all the more difficult to argue the case to Western political and corporate leaders for a global health investment.
The rationale for vaccinating for Covid is the same rationale we should use to make the case for eliminating all preventable diseases everywhere as part of preparing ourselves for any future pandemics. Unless we address infectious diseases in one part of the world, they will come back to bite us in another. TB anywhere is TB everywhere — until there is a better vaccine.